mm to inches: Convert millimeters to inches

Answer
0.0393701 in = 1 mm

1 mm = 0.0393701 in. To convert millimeters to inches, multiply by 0.03937007874. To go back, multiply by 25.4 (or divide by 0.03937007874). Millimeters are the standard for drill bits, bolts and engineering drawings outside the US.

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Converted length
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    Formula

    in = mm × 0.03937007874 mm = in × 25.4 10 mm × 0.03937007874 = 0.393701 in

    mm to inches table

    mmin
    1 mm0.0393701 in
    2 mm0.0787402 in
    3 mm0.11811 in
    4 mm0.15748 in
    5 mm0.19685 in
    6 mm0.23622 in
    8 mm0.314961 in
    10 mm0.393701 in
    12 mm0.472441 in
    13 mm0.511811 in
    15 mm0.590551 in
    16 mm0.629921 in
    19 mm0.748031 in
    20 mm0.787402 in
    22 mm0.866142 in
    25 mm0.984252 in
    30 mm1.1811 in
    32 mm1.25984 in
    40 mm1.5748 in
    50 mm1.9685 in
    60 mm2.3622 in
    75 mm2.95276 in
    100 mm3.93701 in
    500 mm19.685 in
    1,000 mm39.3701 in

    Factors from NIST SP 811 and the BIPM SI Brochure; values rounded to 6 significant digits. Reverse: Inches to mm.

    Frequently asked questions

    How many inches is 10 mm?

    10 mm = 0.393701 in.

    How many mm is 1 in?

    1 in = 25.4 mm.

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