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  <xs:element id="ftnt_StockOptionsAndRestrictedStockUnitsOutstandingMember" abstract="true" name="StockOptionsAndRestrictedStockUnitsOutstandingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_CostOfServicesMember" abstract="true" name="CostOfServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_RestrictedStockUnitsAndOptionsMember" abstract="true" name="RestrictedStockUnitsAndOptionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_EarningsPerShareLineItems" abstract="true" name="EarningsPerShareLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_AlaxaIANetworksCorporationMember" abstract="true" name="AlaxaIANetworksCorporationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_PanoptaHoldingsLLCMember" abstract="true" name="PanoptaHoldingsLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_LinksysMember" abstract="true" name="LinksysMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_USAndCanadaMember" abstract="true" name="USAndCanadaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_ConcentrationRiskPolicyTextBlock" abstract="false" name="ConcentrationRiskPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_EarningsPerShareBasicAndDilutedEPSAbstract" abstract="true" name="EarningsPerShareBasicAndDilutedEPSAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_WarrantiesLineItems" abstract="true" name="WarrantiesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_RevenueRecognitionPeriod" abstract="false" name="RevenueRecognitionPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ftnt_FinancialInstrumentsAndFairValueAbstract" abstract="true" name="FinancialInstrumentsAndFairValueAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_NumberOfSegmentManagersResponsibleForOperations" abstract="false" name="NumberOfSegmentManagersResponsibleForOperations" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ftnt_StateJurisdictionCaliforniaMember" abstract="true" name="StateJurisdictionCaliforniaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_HardwareProductWarrantyMember" abstract="true" name="HardwareProductWarrantyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_EffectiveIncomeTaxRateReconciliationForeignTaxCreditRegulationAdjustmentAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationForeignTaxCreditRegulationAdjustmentAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_DeferredTaxAssetsOperatingLeaseLiabilities" abstract="false" name="DeferredTaxAssetsOperatingLeaseLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_CostOfGoodsSoldMember" abstract="true" name="CostOfGoodsSoldMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_NumberOfBusinessActivities" abstract="false" name="NumberOfBusinessActivities" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ftnt_DefinedContributionPlanEmployerMatchingContributionAmount" abstract="false" name="DefinedContributionPlanEmployerMatchingContributionAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_ValuationAllowanceDeferredTaxAssetsRelatedToEquityMethodInvestmentIncreaseDecreaseAmount" abstract="false" name="ValuationAllowanceDeferredTaxAssetsRelatedToEquityMethodInvestmentIncreaseDecreaseAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_SalesCommissionsMember" abstract="true" name="SalesCommissionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_OperatingLeaseRemainingLeaseTerm" abstract="false" name="OperatingLeaseRemainingLeaseTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ftnt_LongTermInvestmentsLineItemMember" abstract="true" name="LongTermInvestmentsLineItemMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_ScheduleofEstimatedUsefulLivesofPropertyPlantandEquipmentTableTextBlock" abstract="false" name="ScheduleofEstimatedUsefulLivesofPropertyPlantandEquipmentTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_TransfersofEvaluationUnitsfromInventorytoPropertyandEquipment" abstract="false" name="TransfersofEvaluationUnitsfromInventorytoPropertyandEquipment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_OtherAmericasMember" abstract="true" name="OtherAmericasMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_CashFlowLesseeAbstract" abstract="true" name="CashFlowLesseeAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_StockPlan2009Member" abstract="true" name="StockPlan2009Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_AvailableForSaleSecuritiesDebtMaturitiesAfterOneYearFairValue" abstract="false" name="AvailableForSaleSecuritiesDebtMaturitiesAfterOneYearFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_ScheduleOfWarrantiesTable" abstract="true" name="ScheduleOfWarrantiesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_CashandCashEquivalentsandAvailableforSaleInvestmentsPolicyTextBlock" abstract="false" name="CashandCashEquivalentsandAvailableforSaleInvestmentsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_ShareRepurchaseProgramMember" abstract="true" name="ShareRepurchaseProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_DeferredTaxesLineItems" abstract="true" name="DeferredTaxesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_AssetsAndLiabilitiesLesseeTableTextBlock" abstract="false" name="AssetsAndLiabilitiesLesseeTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_TechnicalSupportAndOtherMember" abstract="true" name="TechnicalSupportAndOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_IncomeTaxBenefitFromStockOptionPlansTableTextBlock" abstract="false" name="IncomeTaxBenefitFromStockOptionPlansTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_WarrantyLength" abstract="false" name="WarrantyLength" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ftnt_PriceRangeThreeMember" abstract="true" name="PriceRangeThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_PresentationAndPreparationOfConsolidatedFinancialStatementsPolicyTextBlock" abstract="false" name="PresentationAndPreparationOfConsolidatedFinancialStatementsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_SecuritySubscriptionMember" abstract="true" name="SecuritySubscriptionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_PriceRangeOneMember" abstract="true" name="PriceRangeOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_ReservedForFutureOptionRestrictedStockUnitAndOtherEquityAwardGrantsMember" abstract="true" name="ReservedForFutureOptionRestrictedStockUnitAndOtherEquityAwardGrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_PriceRangeFourMember" abstract="true" name="PriceRangeFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_StockIssuedDuringPeriodValueEquityIncentivePlansNetofTaxesWithheld" abstract="false" name="StockIssuedDuringPeriodValueEquityIncentivePlansNetofTaxesWithheld" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActDeductionForeignDerivedIntangibleIncomeAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActDeductionForeignDerivedIntangibleIncomeAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_CommissionsExpenseTable" abstract="true" name="CommissionsExpenseTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_ShortTermInvestmentsLineItemMember" abstract="true" name="ShortTermInvestmentsLineItemMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_EmployeeMember" abstract="true" name="EmployeeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_ScheduleofSharebasedCompensationSharesWithheldforTaxesTableTextBlock" abstract="false" name="ScheduleofSharebasedCompensationSharesWithheldforTaxesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_ScheduleofEmployeeServiceSharebasedCompensationAllocationofRecognizedPeriodCostsbyAwardTypeTableTextBlock" abstract="false" name="ScheduleofEmployeeServiceSharebasedCompensationAllocationofRecognizedPeriodCostsbyAwardTypeTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_MarketableEquitySecuritiesLineItemMember" abstract="true" name="MarketableEquitySecuritiesLineItemMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_EuropeMiddleEastAndAfricaMember" abstract="true" name="EuropeMiddleEastAndAfricaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_DeferredTaxAssetsResearchAndDevelopmentCapitalized" abstract="false" name="DeferredTaxAssetsResearchAndDevelopmentCapitalized" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_ScheduleOfDeferredTaxesTable" abstract="true" name="ScheduleOfDeferredTaxesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_A2026SeniorNotesMember" abstract="true" name="A2026SeniorNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_DistributorCMember" abstract="true" name="DistributorCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_StockIssuedDuringPeriodSharesEquityIncentivePlans" abstract="false" name="StockIssuedDuringPeriodSharesEquityIncentivePlans" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ftnt_InvestmentsClassificationAsShortTermMaximumOriginalMaturity" abstract="false" name="InvestmentsClassificationAsShortTermMaximumOriginalMaturity" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumStockOwnershipPercentTriggeringEarlyAwardExpiration" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumStockOwnershipPercentTriggeringEarlyAwardExpiration" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ftnt_ScheduleOfAmortizedCostsUnrealizedGainsAndLossesAndFairValueOfAvailableForSaleSecuritiesTableTextBlock" abstract="false" name="ScheduleOfAmortizedCostsUnrealizedGainsAndLossesAndFairValueOfAvailableForSaleSecuritiesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_GainLossFromMutualCovenantNotToSueAgreementRightToUseExistingIntellectualProperty" abstract="false" name="GainLossFromMutualCovenantNotToSueAgreementRightToUseExistingIntellectualProperty" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_DistributorBMember" abstract="true" name="DistributorBMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofPrimaryStockIncentivePlans" abstract="false" name="SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofPrimaryStockIncentivePlans" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ftnt_EquityMethodInvestmentShareOfLossesOfInvesteeAndAmortizationOfDifferenceBetweenCarryingAmountAndUnderlyingEquity" abstract="false" name="EquityMethodInvestmentShareOfLossesOfInvesteeAndAmortizationOfDifferenceBetweenCarryingAmountAndUnderlyingEquity" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_DebtSecuritiesAvailableforsaleContinuousUnrealizedLossPositionAbstract" abstract="true" name="DebtSecuritiesAvailableforsaleContinuousUnrealizedLossPositionAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumStockOwnershipPercentForOptionsGrantedToIndividuals" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumStockOwnershipPercentForOptionsGrantedToIndividuals" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ftnt_PriceRangeTwoMember" abstract="true" name="PriceRangeTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_MoneyMarketFundsExcludingCommercialPaperMember" abstract="true" name="MoneyMarketFundsExcludingCommercialPaperMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_StockRepurchaseProgramAuthorizedAmountApprovedIncrease" abstract="false" name="StockRepurchaseProgramAuthorizedAmountApprovedIncrease" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExercisePriceAsPercentOfFairValueOnGrantDate" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExercisePriceAsPercentOfFairValueOnGrantDate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpirationPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpirationPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ftnt_StockOptionsNonqualifyingMember" abstract="true" name="StockOptionsNonqualifyingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_EffectiveIncomeTaxRateReconciliationForeignWithholdingTaxesAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationForeignWithholdingTaxesAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftnt_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsAndAllocationOfRecognizedPeriodCostsTableTextBlock" abstract="false" name="ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsAndAllocationOfRecognizedPeriodCostsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_InvestmentsClassificationAsShortTermMinimumOriginalMaturity" abstract="false" name="InvestmentsClassificationAsShortTermMinimumOriginalMaturity" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ftnt_RevenuefromContractwithCustomersGeneralInvoicePayablePeriod" abstract="false" name="RevenuefromContractwithCustomersGeneralInvoicePayablePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ftnt_ScheduleOfSharesReservedForFutureIssuanceTableTextBlock" abstract="false" name="ScheduleOfSharesReservedForFutureIssuanceTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ftnt_DirectorsAndOtherServiceProvidersMember" abstract="true" name="DirectorsAndOtherServiceProvidersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_EvaluationUnitsMember" abstract="true" name="EvaluationUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_SoftwareProductWarrantyMember" abstract="true" name="SoftwareProductWarrantyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_CashEquivalentsLineItemMember" abstract="true" name="CashEquivalentsLineItemMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftnt_ScheduleOfEarningsPerShareTable" abstract="true" name="ScheduleOfEarningsPerShareTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="ftnt_IndividualOwningLessThan10PercentOfStockMember" abstract="true" name="IndividualOwningLessThan10PercentOfStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
