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
    #97Number0.00590.150
    #96Number0.00630.160
    #95Number0.00670.170
    #94Number0.00710.180
    #93Number0.00750.190
    #92Number0.00790.201
    #91Number0.00830.211
    #90Number0.00870.221
    #89Number0.00910.231
    #88Number0.00950.241
    #87Number0.01000.254
    #86Number0.01050.267
    #85Number0.01100.279
    #84Number0.01150.292
    #83Number0.01200.305
    #82Number0.01250.318
    #81Number0.01300.330
    #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 & Thread % CalculatorPercent of thread for any drill (cut and form taps), 75 / 65 / 50% tap drills, UNC / UNF / metric chart with thread limits, every thread to 4 in and M64, pipe taps and STI / Helicoil.Unit ConverterLength, weight, pressure, temperature, torque, and speed.

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