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  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2026"
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  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <link:schemaRef
      xlink:href="https://xbrl.sec.gov/ffd/2026/ffd-2026.xsd"
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    <context id="rc">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001439725</identifier>
        </entity>
        <period>
            <startDate>2026-05-18</startDate>
            <endDate>2026-05-18</endDate>
        </period>
    </context>
    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001439725</identifier>
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                <xbrldi:typedMember dimension="ffd:OfferingAxis">
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        <period>
            <startDate>2026-05-18</startDate>
            <endDate>2026-05-18</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">S-3</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-332">S-3</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-333">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-334">0001439725</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-335">BIODESIX INC</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
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    <ffd:FormTp contextRef="rc" id="ixv-363">S-3</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-364">BIODESIX INC</dei:EntityRegistrantName>
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      unitRef="Shares">375000</ffd:AmtSctiesRegd>
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-370"
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-371"
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      contextRef="offrl_1"
      decimals="7"
      id="ixv-372"
      unitRef="pure">0.0001381</ffd:FeeRate>
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-373"
      unitRef="USD">749.37</ffd:FeeAmt>
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    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-375" unitRef="USD">749.37</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">749.37</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-379">(1) The selling stockholder of Biodesix, Inc. (the "Registrant") is registering 375,000 shares of common stock, par value $0.001 per share (the "Common Stock"), that may be issued pursuant to the prospectus to which this exhibit is attached. Pursuant to Rule 416 under the Securities Act of 1933, as amended, this registration statement also covers such an indeterminate amount of shares of common stock as may become issuable to prevent dilution resulting from stock splits, stock dividends and similar events. (2) Estimated solely for the purpose of calculating the registration fee, based on the average of the high and low prices of the shares of Common Stock on The NASDAQ Global Market on May 14, 2026 (such date being within five business days of the date that this registration statement was first filed with the Securities and Exchange Commission, in accordance with Rule 457(c) under the Securities Act).</ffd:OfferingNote>
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