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            <identifier scheme="http://www.sec.gov/CIK">0001798562</identifier>
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        <period>
            <startDate>2026-03-31</startDate>
            <endDate>2026-03-31</endDate>
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    <context id="offrl_1">
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            <identifier scheme="http://www.sec.gov/CIK">0001798562</identifier>
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            <startDate>2026-03-31</startDate>
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        <measure>iso4217:USD</measure>
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    <unit id="pure">
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        <measure>shares</measure>
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    <ffd:FormTp contextRef="rc" id="ixv-168">S-8</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-169">S-8</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-170">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-171">0001798562</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-172">TMC the metals Co Inc.</dei:EntityRegistrantName>
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      contextRef="offrl_1"
      decimals="2"
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      contextRef="offrl_1"
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      unitRef="pure">0.0001381</ffd:FeeRate>
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    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-212" unitRef="USD">0.00</ffd:TtlOffsetAmt>
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    <ffd:OfferingNote contextRef="offrl_1" id="ixv-214">1(a). Represents common shares, without par value ("Common Shares"), that may be issued under the TMC the metals company Inc. 2021 Incentive Equity Plan, as amended (the "Plan"). Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the "Securities Act"), this registration statement shall also cover any additional Common Shares that become issuable under the Plan as a result of any stock dividend, stock split, recapitalization or similar transaction effected without the receipt of consideration that results in an increase to the number of outstanding Common Shares.

1(b). Represents the number of additional Common Shares reserved for issuance under the Plan as a result of the automatic increase in the number of shares reserved under the Plan on January 1, 2026.

1(c). Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(c) and Rule 457(h) promulgated under the Securities Act. The proposed maximum offering price per share and the proposed maximum aggregate offering price are based on the average of the high and the low price of Registrant's Common Shares as reported on the Nasdaq Stock Market LLC on March 30, 2026.</ffd:OfferingNote>
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