<SEC-DOCUMENT>0001307581-25-000014.txt : 20250825
<SEC-HEADER>0001307581-25-000014.hdr.sgml : 20250825
<ACCEPTANCE-DATETIME>20250825162157
ACCESSION NUMBER:		0001307581-25-000014
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250821
FILED AS OF DATE:		20250825
DATE AS OF CHANGE:		20250825

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SANTI ERNEST SCOTT
		CENTRAL INDEX KEY:			0001307581
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-04797
		FILM NUMBER:		251251179

	MAIL ADDRESS:	
		STREET 1:		ILLINOIS TOOL WORKS INC.
		STREET 2:		155 HARLEM AVE.
		CITY:			GLENVIEW
		STATE:			IL
		ZIP:			60025

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ILLINOIS TOOL WORKS INC
		CENTRAL INDEX KEY:			0000049826
		STANDARD INDUSTRIAL CLASSIFICATION:	GENERAL INDUSTRIAL MACHINERY & EQUIPMENT [3560]
		ORGANIZATION NAME:           	06 Technology
		EIN:				361258310
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		155 HARLEM AVENUE
		CITY:			GLENVIEW
		STATE:			IL
		ZIP:			60025
		BUSINESS PHONE:		8477247500

	MAIL ADDRESS:	
		STREET 1:		155 HARLEM AVENUE
		CITY:			GLENVIEW
		STATE:			IL
		ZIP:			60025
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wk-form4_1756153313.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-08-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000049826</issuerCik>
        <issuerName>ILLINOIS TOOL WORKS INC</issuerName>
        <issuerTradingSymbol>ITW</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001307581</rptOwnerCik>
            <rptOwnerName>SANTI ERNEST SCOTT</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ILLINOIS TOOL WORKS INC.</rptOwnerStreet1>
            <rptOwnerStreet2>155 HARLEM AVENUE</rptOwnerStreet2>
            <rptOwnerCity>GLENVIEW</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60025</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-08-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3790</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>258564</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Includes 4,545 shares of deferred stock under the ITW Directors' Deferred Fee Plan as of August 21, 2025.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Christopher P. Rauch, Attorney-in-Fact for E. Scott Santi</signatureName>
        <signatureDate>2025-08-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
