<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with Wdesk from Workiva-->
<!--Copyright 2022 Workiva-->
<!--r:3e31027d-2213-42d9-93fd-324d8c165bfd,g:2bfecaa2-6040-46d9-8b1b-d06f2cac4d68-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETS" xlink:type="simple" xlink:href="tndm-20220630.xsd#CONDENSEDCONSOLIDATEDBALANCESHEETS"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_dad3f423-77cf-4bf3-ae55-9c76dc98c6f2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_d67446c6-e195-4435-9b39-83e128f49820" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AssetsCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_dad3f423-77cf-4bf3-ae55-9c76dc98c6f2" xlink:to="loc_us-gaap_AssetsCurrent_d67446c6-e195-4435-9b39-83e128f49820" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_8da8c2d1-9011-4295-bc5c-c904c701decf" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_dad3f423-77cf-4bf3-ae55-9c76dc98c6f2" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_8da8c2d1-9011-4295-bc5c-c904c701decf" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_460c7dbf-85ff-404a-ae79-69071d752b95" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_dad3f423-77cf-4bf3-ae55-9c76dc98c6f2" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_460c7dbf-85ff-404a-ae79-69071d752b95" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_f9983b97-2b2f-45e8-a812-d6b1ea320ae1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherAssetsNoncurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_dad3f423-77cf-4bf3-ae55-9c76dc98c6f2" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_f9983b97-2b2f-45e8-a812-d6b1ea320ae1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_a7851de3-cc37-4eba-a3e2-2fdf5f05161f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_496efb32-e9b9-43a2-b558-e86b62734e5e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CommonStockValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_a7851de3-cc37-4eba-a3e2-2fdf5f05161f" xlink:to="loc_us-gaap_CommonStockValue_496efb32-e9b9-43a2-b558-e86b62734e5e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalCommonStock_7fe64d9e-eff0-4676-8b54-aa598d886bb6" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AdditionalPaidInCapitalCommonStock"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_a7851de3-cc37-4eba-a3e2-2fdf5f05161f" xlink:to="loc_us-gaap_AdditionalPaidInCapitalCommonStock_7fe64d9e-eff0-4676-8b54-aa598d886bb6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_565ade15-3e72-4e53-a0a2-dfc1ae284add" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_a7851de3-cc37-4eba-a3e2-2fdf5f05161f" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_565ade15-3e72-4e53-a0a2-dfc1ae284add" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_c7fc6ecf-9674-42f6-83ff-33120d892554" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_a7851de3-cc37-4eba-a3e2-2fdf5f05161f" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_c7fc6ecf-9674-42f6-83ff-33120d892554" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_8b9dd49a-f5c4-424f-a815-45fb2a40edde" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_c4b11ffa-578d-484b-b500-e94e5f96a412" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_Liabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_8b9dd49a-f5c4-424f-a815-45fb2a40edde" xlink:to="loc_us-gaap_Liabilities_c4b11ffa-578d-484b-b500-e94e5f96a412" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingencies_1b21ebc8-52d3-4a2c-8c5a-832ee9f39c10" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CommitmentsAndContingencies"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_8b9dd49a-f5c4-424f-a815-45fb2a40edde" xlink:to="loc_us-gaap_CommitmentsAndContingencies_1b21ebc8-52d3-4a2c-8c5a-832ee9f39c10" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_26b5a977-00d2-477b-bc09-bd4bfd4b0837" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockholdersEquity"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_8b9dd49a-f5c4-424f-a815-45fb2a40edde" xlink:to="loc_us-gaap_StockholdersEquity_26b5a977-00d2-477b-bc09-bd4bfd4b0837" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_bedac54e-ab0a-4320-bc3f-2d5fc670a4d1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_Liabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtNoncurrent_9207c6ea-cf76-416f-8e71-954dea4e2db1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConvertibleDebtNoncurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_bedac54e-ab0a-4320-bc3f-2d5fc670a4d1" xlink:to="loc_us-gaap_ConvertibleDebtNoncurrent_9207c6ea-cf76-416f-8e71-954dea4e2db1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_2016d458-4e34-40c1-b4d4-c2a708b7123d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_bedac54e-ab0a-4320-bc3f-2d5fc670a4d1" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_2016d458-4e34-40c1-b4d4-c2a708b7123d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_224358dc-98cc-4704-a60f-8c20f4a5def1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherLiabilitiesNoncurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_bedac54e-ab0a-4320-bc3f-2d5fc670a4d1" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_224358dc-98cc-4704-a60f-8c20f4a5def1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_a496e7aa-22f4-400f-a39a-ba957fbf07b7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_bedac54e-ab0a-4320-bc3f-2d5fc670a4d1" xlink:to="loc_us-gaap_LiabilitiesCurrent_a496e7aa-22f4-400f-a39a-ba957fbf07b7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityNoncurrent_acda8281-34a8-4b95-a245-6571c76697b7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ContractWithCustomerLiabilityNoncurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_bedac54e-ab0a-4320-bc3f-2d5fc670a4d1" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityNoncurrent_acda8281-34a8-4b95-a245-6571c76697b7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_d3002d3e-3b3c-47bf-a9b7-a5671b168e27" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableCurrent_add56fda-b258-4a60-b1ed-808b6d5f7c62" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccountsPayableCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_d3002d3e-3b3c-47bf-a9b7-a5671b168e27" xlink:to="loc_us-gaap_AccountsPayableCurrent_add56fda-b258-4a60-b1ed-808b6d5f7c62" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_eb918a81-c507-4d89-8e54-e2bdf67b96b1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_d3002d3e-3b3c-47bf-a9b7-a5671b168e27" xlink:to="loc_us-gaap_AccruedLiabilitiesCurrent_eb918a81-c507-4d89-8e54-e2bdf67b96b1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_e73cafd5-edf2-47b2-975d-b89ac1ae6cc5" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_d3002d3e-3b3c-47bf-a9b7-a5671b168e27" xlink:to="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_e73cafd5-edf2-47b2-975d-b89ac1ae6cc5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityCurrent_22d261c2-8e00-4db2-811c-cb9612b1b478" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ContractWithCustomerLiabilityCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_d3002d3e-3b3c-47bf-a9b7-a5671b168e27" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityCurrent_22d261c2-8e00-4db2-811c-cb9612b1b478" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrent_110dde7c-0326-4a9f-b0c2-469a63bc43ce" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingLeaseLiabilityCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_d3002d3e-3b3c-47bf-a9b7-a5671b168e27" xlink:to="loc_us-gaap_OperatingLeaseLiabilityCurrent_110dde7c-0326-4a9f-b0c2-469a63bc43ce" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesCurrent_97de265c-666d-4356-b6a3-42d5375b9b74" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherLiabilitiesCurrent"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_d3002d3e-3b3c-47bf-a9b7-a5671b168e27" xlink:to="loc_us-gaap_OtherLiabilitiesCurrent_97de265c-666d-4356-b6a3-42d5375b9b74" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_a9fe16c4-fdf0-4752-8f1f-88f21a4300b0" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AssetsCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_257a68d4-76c1-4e0c-b993-6c1633aed663" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_a9fe16c4-fdf0-4752-8f1f-88f21a4300b0" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_257a68d4-76c1-4e0c-b993-6c1633aed663" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermInvestments_9108fb69-3a7a-4032-a4f4-00f940510b0f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShortTermInvestments"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_a9fe16c4-fdf0-4752-8f1f-88f21a4300b0" xlink:to="loc_us-gaap_ShortTermInvestments_9108fb69-3a7a-4032-a4f4-00f940510b0f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_95b55fa2-a413-4481-b493-6ac5428875c4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_a9fe16c4-fdf0-4752-8f1f-88f21a4300b0" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_95b55fa2-a413-4481-b493-6ac5428875c4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_4db9e1ab-7986-4caa-8d12-da9407b3d7ad" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InventoryNet"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_a9fe16c4-fdf0-4752-8f1f-88f21a4300b0" xlink:to="loc_us-gaap_InventoryNet_4db9e1ab-7986-4caa-8d12-da9407b3d7ad" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_823b5e7f-00c0-4492-bd15-ab62bceab395" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_a9fe16c4-fdf0-4752-8f1f-88f21a4300b0" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_823b5e7f-00c0-4492-bd15-ab62bceab395" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONSANDCOMPREHENSIVEINCOMELOSS" xlink:type="simple" xlink:href="tndm-20220630.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONSANDCOMPREHENSIVEINCOMELOSS"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONSANDCOMPREHENSIVEINCOMELOSS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_830d66f3-1f7a-4d99-b5fb-cdd650c6d8f1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_1fb15d97-9ded-48e6-a561-3cf695107100" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_NetIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_830d66f3-1f7a-4d99-b5fb-cdd650c6d8f1" xlink:to="loc_us-gaap_NetIncomeLoss_1fb15d97-9ded-48e6-a561-3cf695107100" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_40344110-e672-41f7-8ace-579152e69123" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_830d66f3-1f7a-4d99-b5fb-cdd650c6d8f1" xlink:to="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_40344110-e672-41f7-8ace-579152e69123" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_89349ede-e137-41b9-bb79-67307204a5ac" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_830d66f3-1f7a-4d99-b5fb-cdd650c6d8f1" xlink:to="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_89349ede-e137-41b9-bb79-67307204a5ac" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpenses_f2241e4c-47b4-48b3-9760-5b47f91fd072" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingExpenses"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_2a87df0d-1a01-4f8f-adc3-fa71e10cac11" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ResearchAndDevelopmentExpense"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_f2241e4c-47b4-48b3-9760-5b47f91fd072" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_2a87df0d-1a01-4f8f-adc3-fa71e10cac11" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_1d5964f1-a2a6-470a-b041-149794c26c46" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SellingGeneralAndAdministrativeExpense"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_f2241e4c-47b4-48b3-9760-5b47f91fd072" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_1d5964f1-a2a6-470a-b041-149794c26c46" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_78e75bdc-4aa7-4c1c-9178-f37e1a68f7d2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_GrossProfit"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_adfe6e88-9d3e-49a2-863e-06e6350ff050" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_GrossProfit_78e75bdc-4aa7-4c1c-9178-f37e1a68f7d2" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_adfe6e88-9d3e-49a2-863e-06e6350ff050" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_31e023f0-0d11-4ae4-a938-0ceaccc72411" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_GrossProfit_78e75bdc-4aa7-4c1c-9178-f37e1a68f7d2" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_31e023f0-0d11-4ae4-a938-0ceaccc72411" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_0e5a127e-bb59-4fba-a99e-200451e292f6" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_811df6f5-a165-4973-aa34-92e10976c8af" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_0e5a127e-bb59-4fba-a99e-200451e292f6" xlink:to="loc_us-gaap_OperatingIncomeLoss_811df6f5-a165-4973-aa34-92e10976c8af" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_e741aba7-29fb-4ce2-8535-c026b9d188c4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_0e5a127e-bb59-4fba-a99e-200451e292f6" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_e741aba7-29fb-4ce2-8535-c026b9d188c4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_93dac3f3-7428-4075-9b81-a8d153f3f0c7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_67f98bd3-7017-4b90-b584-bfe31778a7bd" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_93dac3f3-7428-4075-9b81-a8d153f3f0c7" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_67f98bd3-7017-4b90-b584-bfe31778a7bd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_0518db55-1acf-41cf-b668-85d148593621" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_93dac3f3-7428-4075-9b81-a8d153f3f0c7" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_0518db55-1acf-41cf-b668-85d148593621" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_e92bb888-ba84-41f3-b07c-ded2adeb6347" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_0dea4ce4-d053-4e16-bcb4-a1463a505f39" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_GrossProfit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_e92bb888-ba84-41f3-b07c-ded2adeb6347" xlink:to="loc_us-gaap_GrossProfit_0dea4ce4-d053-4e16-bcb4-a1463a505f39" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpenses_570f57a8-42ab-4ca0-a2e2-45c6273dc6f1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingExpenses"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_e92bb888-ba84-41f3-b07c-ded2adeb6347" xlink:to="loc_us-gaap_OperatingExpenses_570f57a8-42ab-4ca0-a2e2-45c6273dc6f1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_c05b6516-0b71-438a-b770-1e6655376974" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndOtherIncome_043ea656-5dd1-4ac4-b0b1-c89482650554" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestAndOtherIncome"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpense_c05b6516-0b71-438a-b770-1e6655376974" xlink:to="loc_us-gaap_InterestAndOtherIncome_043ea656-5dd1-4ac4-b0b1-c89482650554" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseOther_3cfb97ce-5bba-4cf4-bee7-1ec01a2676c5" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestExpenseOther"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpense_c05b6516-0b71-438a-b770-1e6655376974" xlink:to="loc_us-gaap_InterestExpenseOther_3cfb97ce-5bba-4cf4-bee7-1ec01a2676c5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAdjustmentOfWarrants_12ec090e-f4b4-4915-b302-e025eaf94be0" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueAdjustmentOfWarrants"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpense_c05b6516-0b71-438a-b770-1e6655376974" xlink:to="loc_us-gaap_FairValueAdjustmentOfWarrants_12ec090e-f4b4-4915-b302-e025eaf94be0" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWS" xlink:type="simple" xlink:href="tndm-20220630.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWS"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_b8a90005-7f97-4c4b-9a57-b2d9b18ba6f6" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_21101938-3876-440a-87b5-736e3672b21b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_b8a90005-7f97-4c4b-9a57-b2d9b18ba6f6" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_21101938-3876-440a-87b5-736e3672b21b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromWarrantExercises_13cf5ed5-656d-4fe3-ae0c-8b65dfc089ee" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProceedsFromWarrantExercises"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_b8a90005-7f97-4c4b-9a57-b2d9b18ba6f6" xlink:to="loc_us-gaap_ProceedsFromWarrantExercises_13cf5ed5-656d-4fe3-ae0c-8b65dfc089ee" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_ff77b513-8422-460b-b684-f67f07ac7b81" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProceedsFromPaymentsForOtherFinancingActivities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_b8a90005-7f97-4c4b-9a57-b2d9b18ba6f6" xlink:to="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_ff77b513-8422-460b-b684-f67f07ac7b81" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_e6005395-1e4a-4c5c-9ee4-025a79a4c09c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_ebe551fe-13a6-4bd2-94b0-6107e3910727" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_e6005395-1e4a-4c5c-9ee4-025a79a4c09c" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_ebe551fe-13a6-4bd2-94b0-6107e3910727" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfShorttermInvestments_95300577-3040-4cad-9231-72c11aa7564d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfShorttermInvestments"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_e6005395-1e4a-4c5c-9ee4-025a79a4c09c" xlink:to="loc_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfShorttermInvestments_95300577-3040-4cad-9231-72c11aa7564d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_tndm_PaymentsToAcquireIntangibleAssetsAndEquityInvestments_b551b4af-8324-4604-b5ea-cbc97dbd75b9" xlink:href="tndm-20220630.xsd#tndm_PaymentsToAcquireIntangibleAssetsAndEquityInvestments"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_e6005395-1e4a-4c5c-9ee4-025a79a4c09c" xlink:to="loc_tndm_PaymentsToAcquireIntangibleAssetsAndEquityInvestments_b551b4af-8324-4604-b5ea-cbc97dbd75b9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireShortTermInvestments_65eb8308-3ff9-4aab-be70-086ba8f4bf4b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PaymentsToAcquireShortTermInvestments"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_e6005395-1e4a-4c5c-9ee4-025a79a4c09c" xlink:to="loc_us-gaap_PaymentsToAcquireShortTermInvestments_65eb8308-3ff9-4aab-be70-086ba8f4bf4b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfShortTermInvestments_890d7680-4624-4951-a73e-11826ea238a5" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProceedsFromSaleOfShortTermInvestments"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_e6005395-1e4a-4c5c-9ee4-025a79a4c09c" xlink:to="loc_us-gaap_ProceedsFromSaleOfShortTermInvestments_890d7680-4624-4951-a73e-11826ea238a5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_c0ff6908-3d1e-41e4-9126-15ffd3586360" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_714f4a5e-bbec-4509-bc82-6497c37a8e85" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_c0ff6908-3d1e-41e4-9126-15ffd3586360" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_714f4a5e-bbec-4509-bc82-6497c37a8e85" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_fb2be0d1-df18-4b45-9731-4f17d4f5a598" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_c0ff6908-3d1e-41e4-9126-15ffd3586360" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_fb2be0d1-df18-4b45-9731-4f17d4f5a598" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_e6ad0c84-3c84-4927-b42d-91e537f37d64" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_c0ff6908-3d1e-41e4-9126-15ffd3586360" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_e6ad0c84-3c84-4927-b42d-91e537f37d64" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_1a75fd3e-6b09-4616-8a7c-4425db60c320" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_c0ff6908-3d1e-41e4-9126-15ffd3586360" xlink:to="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_1a75fd3e-6b09-4616-8a7c-4425db60c320" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_61ed0daf-6783-4fe3-b528-e606dda75a58" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProfitLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_ProfitLoss_61ed0daf-6783-4fe3-b528-e606dda75a58" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_28e7547a-0a20-4b36-b6f7-55fd2593929f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_28e7547a-0a20-4b36-b6f7-55fd2593929f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_2daaba50-5528-43cd-a687-604e61e36d02" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_2daaba50-5528-43cd-a687-604e61e36d02" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_b6ae9e5c-f53c-4b64-a6db-7377606a18b0" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_b6ae9e5c-f53c-4b64-a6db-7377606a18b0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForDoubtfulAccounts_7ef44d84-c50c-4bab-81f6-6ce0f320263d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProvisionForDoubtfulAccounts"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_ProvisionForDoubtfulAccounts_7ef44d84-c50c-4bab-81f6-6ce0f320263d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryWriteDown_16e7f761-a689-42bf-8074-51b849787518" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InventoryWriteDown"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_InventoryWriteDown_16e7f761-a689-42bf-8074-51b849787518" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAdjustmentOfWarrants_9b1e3514-cac6-4fb9-a72f-e85b6b574d6e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueAdjustmentOfWarrants"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_FairValueAdjustmentOfWarrants_9b1e3514-cac6-4fb9-a72f-e85b6b574d6e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium_4b8665b1-11e9-49b2-bc7a-bb7658b3237d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium_4b8665b1-11e9-49b2-bc7a-bb7658b3237d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_93eea840-f707-41b4-b687-506dad5a2ccb" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="9" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_ShareBasedCompensation_93eea840-f707-41b4-b687-506dad5a2ccb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherOperatingActivitiesCashFlowStatement_5b108000-9ad6-40c9-bb04-3fc9102ef127" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherOperatingActivitiesCashFlowStatement"/>
    <link:calculationArc order="10" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_OtherOperatingActivitiesCashFlowStatement_5b108000-9ad6-40c9-bb04-3fc9102ef127" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_ff4baf60-6fdd-4ebe-92a2-d72219c4457f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable"/>
    <link:calculationArc order="11" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_ff4baf60-6fdd-4ebe-92a2-d72219c4457f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_75f8eb4c-da2f-4635-b058-ad707b2227d8" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncreaseDecreaseInInventories"/>
    <link:calculationArc order="12" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_IncreaseDecreaseInInventories_75f8eb4c-da2f-4635-b058-ad707b2227d8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_e20766d9-8866-4f06-bcd8-cf2c8eb1ca71" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets"/>
    <link:calculationArc order="13" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_e20766d9-8866-4f06-bcd8-cf2c8eb1ca71" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_2845aacc-43c4-4cc0-959e-081fcfd672a9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentAssets"/>
    <link:calculationArc order="14" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_2845aacc-43c4-4cc0-959e-081fcfd672a9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInEmployeeRelatedLiabilities_73b9e5ce-e873-45c3-9aed-941712061c8c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncreaseDecreaseInEmployeeRelatedLiabilities"/>
    <link:calculationArc order="15" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_IncreaseDecreaseInEmployeeRelatedLiabilities_73b9e5ce-e873-45c3-9aed-941712061c8c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_d0837310-b6c6-40dc-8359-5011a5549287" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability"/>
    <link:calculationArc order="16" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_d0837310-b6c6-40dc-8359-5011a5549287" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingLeaseLiability_9bea6545-0834-4eef-b954-9925f696064b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncreaseDecreaseInOperatingLeaseLiability"/>
    <link:calculationArc order="17" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_IncreaseDecreaseInOperatingLeaseLiability_9bea6545-0834-4eef-b954-9925f696064b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_c397fa5d-085d-4011-92c5-3315a7044990" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities"/>
    <link:calculationArc order="18" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_417f7222-a2e9-4c7b-ad84-ae2ae70cbe09" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_c397fa5d-085d-4011-92c5-3315a7044990" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/SummaryofSignificantAccountingPoliciesReconciliationofChangeinEstimatedWarrantyLiabilitiesDetail" xlink:type="simple" xlink:href="tndm-20220630.xsd#SummaryofSignificantAccountingPoliciesReconciliationofChangeinEstimatedWarrantyLiabilitiesDetail"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/SummaryofSignificantAccountingPoliciesReconciliationofChangeinEstimatedWarrantyLiabilitiesDetail" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductWarrantyAccrual_23fa282c-872b-4be4-854d-fdb0a37875d5" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProductWarrantyAccrual"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductWarrantyAccrualNoncurrent_710dadf6-fe51-4d92-8519-714dcb9defb3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProductWarrantyAccrualNoncurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ProductWarrantyAccrual_23fa282c-872b-4be4-854d-fdb0a37875d5" xlink:to="loc_us-gaap_ProductWarrantyAccrualNoncurrent_710dadf6-fe51-4d92-8519-714dcb9defb3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductWarrantyAccrualClassifiedCurrent_054193b5-ba46-4ded-9393-85c2bfd2138d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProductWarrantyAccrualClassifiedCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ProductWarrantyAccrual_23fa282c-872b-4be4-854d-fdb0a37875d5" xlink:to="loc_us-gaap_ProductWarrantyAccrualClassifiedCurrent_054193b5-ba46-4ded-9393-85c2bfd2138d" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/SummaryofSignificantAccountingPoliciesNumeratorandDenominatoroftheBasicandDilutedNetIncomePerShareComputationsDetails" xlink:type="simple" xlink:href="tndm-20220630.xsd#SummaryofSignificantAccountingPoliciesNumeratorandDenominatoroftheBasicandDilutedNetIncomePerShareComputationsDetails"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/SummaryofSignificantAccountingPoliciesNumeratorandDenominatoroftheBasicandDilutedNetIncomePerShareComputationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_fd624574-00da-47f7-acdb-c7c592914f00" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_8c78140b-616b-4632-a00c-1b5f4f0a811b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_fd624574-00da-47f7-acdb-c7c592914f00" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_8c78140b-616b-4632-a00c-1b5f4f0a811b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_f0b1854f-4e9d-4ad7-a8a0-6aff291d0fe0" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_fd624574-00da-47f7-acdb-c7c592914f00" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_f0b1854f-4e9d-4ad7-a8a0-6aff291d0fe0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToCallOptionsAndWarrants_2e258be4-42c4-433c-8d2b-27c091768315" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncrementalCommonSharesAttributableToCallOptionsAndWarrants"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_fd624574-00da-47f7-acdb-c7c592914f00" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToCallOptionsAndWarrants_2e258be4-42c4-433c-8d2b-27c091768315" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/ShortTermInvestmentsEstimatedFairValueofShortTermInvestmentsDetail" xlink:type="simple" xlink:href="tndm-20220630.xsd#ShortTermInvestmentsEstimatedFairValueofShortTermInvestmentsDetail"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/ShortTermInvestmentsEstimatedFairValueofShortTermInvestmentsDetail" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_fff447de-011e-4728-bece-179b3d9f98f0" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_ef460091-6cf0-4f2c-8aed-0be65f786498" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_fff447de-011e-4728-bece-179b3d9f98f0" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_ef460091-6cf0-4f2c-8aed-0be65f786498" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_4f533a60-e9da-4b3c-8ddd-466e231401df" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_fff447de-011e-4728-bece-179b3d9f98f0" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_4f533a60-e9da-4b3c-8ddd-466e231401df" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_5a7dc6bb-75ec-451e-a70f-2ee2e35618d2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_fff447de-011e-4728-bece-179b3d9f98f0" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_5a7dc6bb-75ec-451e-a70f-2ee2e35618d2" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/ShortTermInvestmentsContractualMaturitiesofAvailableForSaleDebtSecuritiesDetails" xlink:type="simple" xlink:href="tndm-20220630.xsd#ShortTermInvestmentsContractualMaturitiesofAvailableForSaleDebtSecuritiesDetails"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/ShortTermInvestmentsContractualMaturitiesofAvailableForSaleDebtSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_1903a58e-7540-4fb0-90d9-2910c75ead54" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate"/>
    <link:loc xlink:type="locator" xlink:label="loc_tndm_DebtSecuritiesAvailableForSaleFairValueMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughTwo_bc971a55-4c50-4745-a995-48a5574046cf" xlink:href="tndm-20220630.xsd#tndm_DebtSecuritiesAvailableForSaleFairValueMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughTwo"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_1903a58e-7540-4fb0-90d9-2910c75ead54" xlink:to="loc_tndm_DebtSecuritiesAvailableForSaleFairValueMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughTwo_bc971a55-4c50-4745-a995-48a5574046cf" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_8a091e67-1230-49a6-93db-3e11ae3567b7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_1903a58e-7540-4fb0-90d9-2910c75ead54" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_8a091e67-1230-49a6-93db-3e11ae3567b7" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/CompositionofCertainFinancialStatementItemsAccountsReceivableDetails" xlink:type="simple" xlink:href="tndm-20220630.xsd#CompositionofCertainFinancialStatementItemsAccountsReceivableDetails"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/CompositionofCertainFinancialStatementItemsAccountsReceivableDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNet_5f6ef037-51b3-46fc-9692-b150d3d11656" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccountsReceivableNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableGross_1ec1cf16-f2c7-44e9-b4a0-381af2566b98" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccountsReceivableGross"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AccountsReceivableNet_5f6ef037-51b3-46fc-9692-b150d3d11656" xlink:to="loc_us-gaap_AccountsReceivableGross_1ec1cf16-f2c7-44e9-b4a0-381af2566b98" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_63c5be40-7fc1-4f45-9678-496fc032ff2c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivable"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AccountsReceivableNet_5f6ef037-51b3-46fc-9692-b150d3d11656" xlink:to="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_63c5be40-7fc1-4f45-9678-496fc032ff2c" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/CompositionofCertainFinancialStatementItemsInventoryDetail" xlink:type="simple" xlink:href="tndm-20220630.xsd#CompositionofCertainFinancialStatementItemsInventoryDetail"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/CompositionofCertainFinancialStatementItemsInventoryDetail" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_efe98b2c-2d8f-4a1e-a1bf-3c7506e3d35e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InventoryNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryWorkInProcess_0851ba1a-44e0-4fab-a826-d16cb8fab0b7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InventoryWorkInProcess"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_efe98b2c-2d8f-4a1e-a1bf-3c7506e3d35e" xlink:to="loc_us-gaap_InventoryWorkInProcess_0851ba1a-44e0-4fab-a826-d16cb8fab0b7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryFinishedGoods_8e5c3d99-ed21-4fd5-83e0-ef04e27277bc" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InventoryFinishedGoods"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_efe98b2c-2d8f-4a1e-a1bf-3c7506e3d35e" xlink:to="loc_us-gaap_InventoryFinishedGoods_8e5c3d99-ed21-4fd5-83e0-ef04e27277bc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryRawMaterials_eaf9fe8e-dda8-42b5-b610-ceddcae80499" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InventoryRawMaterials"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_efe98b2c-2d8f-4a1e-a1bf-3c7506e3d35e" xlink:to="loc_us-gaap_InventoryRawMaterials_eaf9fe8e-dda8-42b5-b610-ceddcae80499" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/FairValueMeasurementsFinancialAssetsandLiabilitiesMeasuredatFairValueonRecurringBasisDetail" xlink:type="simple" xlink:href="tndm-20220630.xsd#FairValueMeasurementsFinancialAssetsandLiabilitiesMeasuredatFairValueonRecurringBasisDetail"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/FairValueMeasurementsFinancialAssetsandLiabilitiesMeasuredatFairValueonRecurringBasisDetail" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_e5a293f0-7cc6-4f79-8e15-388b21d73349" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantsAndRightsOutstanding_8717ba50-8820-4a41-a8ef-4028ec45a669" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_WarrantsAndRightsOutstanding"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosure_e5a293f0-7cc6-4f79-8e15-388b21d73349" xlink:to="loc_us-gaap_WarrantsAndRightsOutstanding_8717ba50-8820-4a41-a8ef-4028ec45a669" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_6c6debfa-f07c-499b-adf6-0e7a42281c4f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_55b381fb-a93c-4586-8cf2-2a629f229f1f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsFairValueDisclosure_6c6debfa-f07c-499b-adf6-0e7a42281c4f" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_55b381fb-a93c-4586-8cf2-2a629f229f1f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_d225fff5-327b-446d-8285-f8f06e66a628" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsFairValueDisclosure_6c6debfa-f07c-499b-adf6-0e7a42281c4f" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_d225fff5-327b-446d-8285-f8f06e66a628" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/LeasesLeaseCostLeaseTermDiscountRateOperatingLeasesDetails" xlink:type="simple" xlink:href="tndm-20220630.xsd#LeasesLeaseCostLeaseTermDiscountRateOperatingLeasesDetails"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/LeasesLeaseCostLeaseTermDiscountRateOperatingLeasesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseCost_133bd0ee-5a56-40be-9d11-f3d8cf2804e9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LeaseCost"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermLeaseCost_c4ab20fa-0c82-4f2e-9496-2d83fe74f9a9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShortTermLeaseCost"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_133bd0ee-5a56-40be-9d11-f3d8cf2804e9" xlink:to="loc_us-gaap_ShortTermLeaseCost_c4ab20fa-0c82-4f2e-9496-2d83fe74f9a9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseCost_93ed14f6-87af-4d3b-ab26-430e46a480c9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingLeaseCost"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_133bd0ee-5a56-40be-9d11-f3d8cf2804e9" xlink:to="loc_us-gaap_OperatingLeaseCost_93ed14f6-87af-4d3b-ab26-430e46a480c9" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/LeasesFutureMinimumPaymentsUnderNoncancellableOperatingLeasesDetails" xlink:type="simple" xlink:href="tndm-20220630.xsd#LeasesFutureMinimumPaymentsUnderNoncancellableOperatingLeasesDetails"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/LeasesFutureMinimumPaymentsUnderNoncancellableOperatingLeasesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_32818b3d-d6ca-41cf-ac79-fd6757c0f24d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_a626e234-7fbb-47e1-bb43-7400f00ae0eb" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_32818b3d-d6ca-41cf-ac79-fd6757c0f24d" xlink:to="loc_us-gaap_OperatingLeaseLiability_a626e234-7fbb-47e1-bb43-7400f00ae0eb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_808c87a2-76d6-4422-9f75-f64fe5e070c5" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_32818b3d-d6ca-41cf-ac79-fd6757c0f24d" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_808c87a2-76d6-4422-9f75-f64fe5e070c5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_2310d4df-37ae-4d18-a9af-ef5ab21625c4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_b4f72122-3aae-487c-98f2-a76d227941f7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingLeaseLiability_2310d4df-37ae-4d18-a9af-ef5ab21625c4" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_b4f72122-3aae-487c-98f2-a76d227941f7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrent_475046fb-bf9d-4f22-bb09-e9cd752609c4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingLeaseLiabilityCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingLeaseLiability_2310d4df-37ae-4d18-a9af-ef5ab21625c4" xlink:to="loc_us-gaap_OperatingLeaseLiabilityCurrent_475046fb-bf9d-4f22-bb09-e9cd752609c4" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/LeasesFutureMinimumPaymentsUnderNoncancellableOperatingLeasesDetails_1" xlink:type="simple" xlink:href="tndm-20220630.xsd#LeasesFutureMinimumPaymentsUnderNoncancellableOperatingLeasesDetails_1"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/LeasesFutureMinimumPaymentsUnderNoncancellableOperatingLeasesDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_26c2d99e-c099-4f07-8330-5eba49b05862" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_4cb77cfa-2105-418d-ae59-d4261ae78f77" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_26c2d99e-c099-4f07-8330-5eba49b05862" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_4cb77cfa-2105-418d-ae59-d4261ae78f77" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_41e8402c-cb87-4fb0-bd69-9570ac87003e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_26c2d99e-c099-4f07-8330-5eba49b05862" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_41e8402c-cb87-4fb0-bd69-9570ac87003e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_58062f35-5d72-468f-9a16-0a9b7dae7e03" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_26c2d99e-c099-4f07-8330-5eba49b05862" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_58062f35-5d72-468f-9a16-0a9b7dae7e03" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_5a5410bb-be6b-4f9b-973e-55e0f4387df1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_26c2d99e-c099-4f07-8330-5eba49b05862" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_5a5410bb-be6b-4f9b-973e-55e0f4387df1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_336d6d25-45c3-4787-a2e5-12fe0fee5d16" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_26c2d99e-c099-4f07-8330-5eba49b05862" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_336d6d25-45c3-4787-a2e5-12fe0fee5d16" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_tndm_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour_a0fc742e-e3a1-458e-a0b2-a9ad01bdf435" xlink:href="tndm-20220630.xsd#tndm_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_26c2d99e-c099-4f07-8330-5eba49b05862" xlink:to="loc_tndm_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour_a0fc742e-e3a1-458e-a0b2-a9ad01bdf435" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/DebtComponentsofConvertibleNoteDetails" xlink:type="simple" xlink:href="tndm-20220630.xsd#DebtComponentsofConvertibleNoteDetails"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/DebtComponentsofConvertibleNoteDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_ab781cfa-9798-462c-9dea-095ffae1d594" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongTermDebt"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_d43bc75d-d248-4ab4-acb0-0e981a6f1c8a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_ab781cfa-9798-462c-9dea-095ffae1d594" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_d43bc75d-d248-4ab4-acb0-0e981a6f1c8a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_041e493c-dc4e-468c-88ba-3ca9b88eb52e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DeferredFinanceCostsNet"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_ab781cfa-9798-462c-9dea-095ffae1d594" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_041e493c-dc4e-468c-88ba-3ca9b88eb52e" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.tandemdiabetes.com/role/DebtInterestExpenseRecognizedDetails" xlink:type="simple" xlink:href="tndm-20220630.xsd#DebtInterestExpenseRecognizedDetails"/>
  <link:calculationLink xlink:role="http://www.tandemdiabetes.com/role/DebtInterestExpenseRecognizedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_41685b8f-7bc2-4cc1-8eea-dfca656a2848" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestExpenseDebt"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfDebtDiscountPremium_9061d5d3-814d-4a17-93c8-de12c69831b9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AmortizationOfDebtDiscountPremium"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDebt_41685b8f-7bc2-4cc1-8eea-dfca656a2848" xlink:to="loc_us-gaap_AmortizationOfDebtDiscountPremium_9061d5d3-814d-4a17-93c8-de12c69831b9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebtExcludingAmortization_a1ecd4ad-f736-439d-97e5-34c9be2bd0f0" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestExpenseDebtExcludingAmortization"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDebt_41685b8f-7bc2-4cc1-8eea-dfca656a2848" xlink:to="loc_us-gaap_InterestExpenseDebtExcludingAmortization_a1ecd4ad-f736-439d-97e5-34c9be2bd0f0" xlink:type="arc"/>
  </link:calculationLink>
</link:linkbase>
