<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-03-18</periodOfReport>

    <issuer>
        <issuerCik>0000050863</issuerCik>
        <issuerName>INTEL CORP</issuerName>
        <issuerTradingSymbol>INTC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001316331</rptOwnerCik>
            <rptOwnerName>GELSINGER PATRICK P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O INTEL CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>2200 MISSION COLLEGE BLVD</rptOwnerStreet2>
            <rptOwnerCity>SANTA CLARA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95054</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <officerTitle>CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-03-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>156764</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>63.79</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>158244</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">In accordance with the Offer Letter between Intel and reporting person dated January 13, 2021 (&quot;Offer Letter&quot;) (as disclosed in Intel's Current Report on Form 8-K filed with the Securities and Exchange Committee on January 14, 2021), reporting person acquired these shares from Intel, as described in the Offer Letter relating to an optional investment RSU grant.</footnote>
        <footnote id="F2">Reflects the closing price of Intel common stock on March 15, 2021 in accordance with the Offer Letter.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Alex Shukhman, attorney-in-fact</signatureName>
        <signatureDate>2021-03-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
