<SEC-DOCUMENT>0001039399-20-000092.txt : 20201116
<SEC-HEADER>0001039399-20-000092.hdr.sgml : 20201116
<ACCEPTANCE-DATETIME>20201116170940
ACCESSION NUMBER:		0001039399-20-000092
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20201113
FILED AS OF DATE:		20201116
DATE AS OF CHANGE:		20201116

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Obregon-Jimenez Rebeca
		CENTRAL INDEX KEY:			0001788948

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50307
		FILM NUMBER:		201318275

	MAIL ADDRESS:	
		STREET 1:		3748 E MARE COURT
		CITY:			PHOENIX
		STATE:			AZ
		ZIP:			85044

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FORMFACTOR INC
		CENTRAL INDEX KEY:			0001039399
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				133711155
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1226

	BUSINESS ADDRESS:	
		STREET 1:		7005 SOUTHFRONT ROAD
		CITY:			LIVERMORE
		STATE:			CA
		ZIP:			94551
		BUSINESS PHONE:		9252433522

	MAIL ADDRESS:	
		STREET 1:		7005 SOUTHFRONT ROAD
		CITY:			LIVERMORE
		STATE:			CA
		ZIP:			94551
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_160556456728241.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-11-13</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001039399</issuerCik>
        <issuerName>FORMFACTOR INC</issuerName>
        <issuerTradingSymbol>FORM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001788948</rptOwnerCik>
            <rptOwnerName>Obregon-Jimenez Rebeca</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3748 E MARE COURT</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PHOENIZ</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85044</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-11-13</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5992</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>37.5915</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">All shares sold at an exact price.  A breakdown is not applicable.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>By: Jason Cohen, Attorney-in-Factor For: Rebeca Obregon-Jimenez</signatureName>
        <signatureDate>2020-11-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
