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    Drill size chart

    Every number, letter and fractional drill from #80 to 1 inch, sorted by size, with decimal inch and millimeter equivalents.

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    Number, letter and fractional drills by size
    DrillTypeInchmm
    #80Number0.01350.343
    #79Number0.01450.368
    1/64Fraction0.01560.397
    #78Number0.01600.406
    #77Number0.01800.457
    #76Number0.02000.508
    #75Number0.02100.533
    #74Number0.02250.571
    #73Number0.02400.610
    #72Number0.02500.635
    #71Number0.02600.660
    #70Number0.02800.711
    #69Number0.02920.742
    #68Number0.03100.787
    1/32Fraction0.03130.794
    #67Number0.03200.813
    #66Number0.03300.838
    #65Number0.03500.889
    #64Number0.03600.914
    #63Number0.03700.940
    #62Number0.03800.965
    #61Number0.03900.991
    #60Number0.04001.016
    #59Number0.04101.041
    #58Number0.04201.067
    #57Number0.04301.092
    #56Number0.04651.181
    3/64Fraction0.04691.191
    #55Number0.05201.321
    #54Number0.05501.397
    #53Number0.05951.511
    1/16Fraction0.06251.588
    #52Number0.06351.613
    #51Number0.06701.702
    #50Number0.07001.778
    #49Number0.07301.854
    #48Number0.07601.930
    5/64Fraction0.07811.984
    #47Number0.07851.994
    #46Number0.08102.057
    #45Number0.08202.083
    #44Number0.08602.184
    #43Number0.08902.261
    #42Number0.09352.375
    3/32Fraction0.09382.381
    #41Number0.09602.438
    #40Number0.09802.489
    #39Number0.09952.527
    #38Number0.10152.578
    #37Number0.10402.642
    #36Number0.10652.705
    7/64Fraction0.10942.778
    #35Number0.11002.794
    #34Number0.11102.819
    #33Number0.11302.870
    #32Number0.11602.946
    #31Number0.12003.048
    1/8Fraction0.12503.175
    #30Number0.12853.264
    #29Number0.13603.454
    #28Number0.14053.569
    9/64Fraction0.14063.572
    #27Number0.14403.658
    #26Number0.14703.734
    #25Number0.14953.797
    #24Number0.15203.861
    #23Number0.15403.912
    5/32Fraction0.15633.969
    #22Number0.15703.988
    #21Number0.15904.039
    #20Number0.16104.089
    #19Number0.16604.216
    #18Number0.16954.305
    11/64Fraction0.17194.366
    #17Number0.17304.394
    #16Number0.17704.496
    #15Number0.18004.572
    #14Number0.18204.623
    #13Number0.18504.699
    3/16Fraction0.18754.762
    #12Number0.18904.801
    #11Number0.19104.851
    #10Number0.19354.915
    #9Number0.19604.978
    #8Number0.19905.055
    #7Number0.20105.105
    13/64Fraction0.20315.159
    #6Number0.20405.182
    #5Number0.20555.220
    #4Number0.20905.309
    #3Number0.21305.410
    7/32Fraction0.21885.556
    #2Number0.22105.613
    #1Number0.22805.791
    ALetter0.23405.944
    15/64Fraction0.23445.953
    BLetter0.23806.045
    CLetter0.24206.147
    DLetter0.24606.248
    1/4Fraction0.25006.350
    ELetter0.25006.350
    FLetter0.25706.528
    GLetter0.26106.629
    17/64Fraction0.26566.747
    HLetter0.26606.756
    ILetter0.27206.909
    JLetter0.27707.036
    KLetter0.28107.137
    9/32Fraction0.28137.144
    LLetter0.29007.366
    MLetter0.29507.493
    19/64Fraction0.29697.541
    NLetter0.30207.671
    5/16Fraction0.31257.938
    OLetter0.31608.026
    PLetter0.32308.204
    21/64Fraction0.32818.334
    QLetter0.33208.433
    RLetter0.33908.611
    11/32Fraction0.34388.731
    SLetter0.34808.839
    TLetter0.35809.093
    23/64Fraction0.35949.128
    ULetter0.36809.347
    3/8Fraction0.37509.525
    VLetter0.37709.576
    WLetter0.38609.804
    25/64Fraction0.39069.922
    XLetter0.397010.084
    YLetter0.404010.262
    13/32Fraction0.406310.319
    ZLetter0.413010.490
    27/64Fraction0.421910.716
    7/16Fraction0.437511.112
    29/64Fraction0.453111.509
    15/32Fraction0.468811.906
    31/64Fraction0.484412.303
    1/2Fraction0.500012.700
    33/64Fraction0.515613.097
    17/32Fraction0.531313.494
    35/64Fraction0.546913.891
    9/16Fraction0.562514.288
    37/64Fraction0.578114.684
    19/32Fraction0.593815.081
    39/64Fraction0.609415.478
    5/8Fraction0.625015.875
    41/64Fraction0.640616.272
    21/32Fraction0.656316.669
    43/64Fraction0.671917.066
    11/16Fraction0.687517.463
    45/64Fraction0.703117.859
    23/32Fraction0.718818.256
    47/64Fraction0.734418.653
    3/4Fraction0.750019.050
    49/64Fraction0.765619.447
    25/32Fraction0.781319.844
    51/64Fraction0.796920.241
    13/16Fraction0.812520.638
    53/64Fraction0.828121.034
    27/32Fraction0.843821.431
    55/64Fraction0.859421.828
    7/8Fraction0.875022.225
    57/64Fraction0.890622.622
    29/32Fraction0.906323.019
    59/64Fraction0.921923.416
    15/16Fraction0.937523.813
    61/64Fraction0.953124.209
    31/32Fraction0.968824.606
    63/64Fraction0.984425.003
    1Fraction1.000025.400

    Common questions

    What decimal is a #7 drill?
    0.2010 in (5.105 mm) — the 1/4-20 tap drill.
    Which is bigger, a letter or a number drill?
    Number drills run from #80 (0.0135 in) up to #1 (0.228 in); letter drills continue from A (0.234 in) to Z (0.413 in).

    Calculators that use this data

    Drilling CalculationsDrilling RPM, feed per revolution, point allowance and cutting time.Tap Drill ChartRecommended tap drill sizes for UNC, UNF, and metric threads.Unit ConverterLength, weight, pressure, temperature, torque, and speed.

    Read the guide

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