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        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001889823</identifier>
        </entity>
        <period>
            <startDate>2026-07-22</startDate>
            <endDate>2026-07-22</endDate>
        </period>
    </context>
    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001889823</identifier>
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                <xbrldi:typedMember dimension="ffd:OfferingAxis">
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        <period>
            <startDate>2026-07-22</startDate>
            <endDate>2026-07-22</endDate>
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    <unit id="USD">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <unit id="Shares">
        <measure>shares</measure>
    </unit>
    <ffd:FormTp contextRef="rc" id="ixv-331">F-1</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-332">F-1</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-333">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-334">0001889823</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-335">DEFSEC Technologies Inc.</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
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    <ffd:FormTp contextRef="rc" id="ixv-363">F-1</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-364">DEFSEC Technologies Inc.</dei:EntityRegistrantName>
    <ffd:PrevslyPdFlg contextRef="offrl_1" id="ixv-365">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_1" id="ixv-366">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_1" id="ixv-367">Common Shares</ffd:OfferingSctyTitl>
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      contextRef="offrl_1"
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      id="ixv-369"
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-370"
      unitRef="USD">1.76</ffd:MaxOfferingPricPerScty>
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-371"
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      contextRef="offrl_1"
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      unitRef="pure">0.0001381</ffd:FeeRate>
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      contextRef="offrl_1"
      decimals="2"
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    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-375" unitRef="USD">175.85</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="rc" decimals="2" id="ixv-376" unitRef="USD">0.00</ffd:TtlPrevslyPdAmt>
    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-377" unitRef="USD">0.00</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="rc" decimals="2" id="ixv-378" unitRef="USD">175.85</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-379">Pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"), there are also being registered such indeterminate number of additional common shares of DEFSEC Technologies Inc. (the "Common Shares") as may be issued to prevent dilution resulting from share splits, share dividends or similar transactions.

Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(c) of the Securities Act based on the average of the high and low sales price of the Common Shares as reported on the Nasdaq Capital Market on July 21, 2026.

Represents 723,481 Common Shares issuable upon exercise of (a) 673,006 warrants issued to certain investors and (b) 50,475 warrants issued to the placement agent, or its designees, as compensation, in each case, held by the selling securityholders named in the registration statement which this filing fee table relates.</ffd:OfferingNote>
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