[object Object]Engineering Information, Conversions and Calculations

Interactive Drill Size Chart

The drill size chart provides a list of standard size drill bits in several measurement systems, including fractional, metric, wire gauge number, and letter. The decimal equivalents of the diameters are shown in both English and Metric units. Fractional sizes are measured in inches, while metric sizes are measured in millimeters. The wire gauge and letter systems refer to tool diameters that increase as the wire gauge decreases from #107 to #1 and then continues from A to Z

Drill sizeDiameter (in)Diameter (mm)
#107
0.0019
0.0483
0.05 mm
0.0020
0.0500
#106
0.0023
0.0584
#105
0.0027
0.0686
#104
0.0031
0.0787
#103
0.0035
0.0889
#102
0.0039
0.0991
0.1 mm
0.0039
0.1000
#101
0.0043
0.1092
#100
0.0047
0.1194
#99
0.0051
0.1295
#98
0.0055
0.1397
#97
0.0059
0.1499
#96
0.0063
0.1600
#95
0.0067
0.1702
#94
0.0071
0.1803
#93
0.0075
0.1905
0.2 mm
0.0079
0.2000
#92
0.0079
0.2007
#91
0.0083
0.2108
#90
0.0087
0.2210
#89
0.0091
0.2311
#88
0.0095
0.2413
#87
0.0100
0.2540
#86
0.0105
0.2667
#85
0.0110
0.2794
#84
0.0115
0.2921
0.3 mm
0.0118
0.3000
#83
0.0120
0.3048
#82
0.0125
0.3175
#81
0.0130
0.3302
#80
0.0135
0.3429
#79
0.0145
0.3680
1/64 in
0.0156
0.3969
0.4 mm
0.0158
0.4000
#78
0.0160
0.4064
#77
0.0180
0.4572
0.5 mm
0.0197
0.5000
#76
0.0200
0.5080
#75
0.0210
0.5334
#74
0.0225
0.5715
0.6 mm
0.0236
0.6000
#73
0.0240
0.6096
#72
0.0250
0.6350
#71
0.0260
0.6604
0.7 mm
0.0276
0.7000
#70
0.0280
0.7112
#69
0.0292
0.7417
#68
0.0310
0.7874
1/32 in
0.0313
0.7938
0.8 mm
0.0315
0.8000
#67
0.0320
0.8128
#66
0.0330
0.8382
#65
0.0350
0.8890
0.9 mm
0.0354
0.9000
#64
0.0360
0.9144
#63
0.0370
0.9398
#62
0.0380
0.9652
#61
0.0390
0.9906
1 mm
0.0394
1.0000
#60
0.0400
1.0160
#59
0.0410
1.0414
#58
0.0420
1.0668
#57
0.0430
1.0922
1.1 mm
0.0433
1.1000
#56
0.0465
1.1811
3/64 in
0.0469
1.1906
1.2 mm
0.0472
1.2000
1.3 mm
0.0512
1.3000
#55
0.0520
1.3208
#54
0.0550
1.3970
1.4 mm
0.0551
1.4000
1.5 mm
0.0591
1.5000
#53
0.0595
1.5113
1/16 in
0.0625
1.5875
1.6 mm
0.0630
1.6000
#52
0.0635
1.6129
1.7 mm
0.0669
1.7000
#51
0.0670
1.7018
#50
0.0700
1.7780
1.8 mm
0.0709
1.8000
#49
0.0730
1.8542
1.9 mm
0.0748
1.9000
#48
0.0760
1.9304
5/64 in
0.0781
1.9844
#47
0.0785
1.9939
2 mm
0.0787
2.0000
#46
0.0810
2.0574
#45
0.0820
2.0828
2.1 mm
0.0827
2.1000
#44
0.0860
2.1844
2.2 mm
0.0866
2.2000
#43
0.0890
2.2606
2.3 mm
0.0906
2.3000
#42
0.0935
2.3749
3/32 in
0.0938
2.3813
2.4 mm
0.0945
2.4000
#41
0.0960
2.4384
#40
0.0980
2.4892
2.5 mm
0.0984
2.5000
#39
0.0995
2.5273
#38
0.1015
2.5781
2.6 mm
0.1024
2.6000
#37
0.1040
2.6416
2.7 mm
0.1063
2.7000
#36
0.1065
2.7051
7/64 in
0.1094
2.7781
#35
0.1100
2.7940
2.8 mm
0.1102
2.8000
#34
0.1110
2.8194
#33
0.1130
2.8702
2.9 mm
0.1142
2.9000
#32
0.1160
2.9464
3 mm
0.1181
3.0000
#31
0.1200
3.0480
3.1 mm
0.1221
3.1000
1/8 in
0.1250
3.1750
3.2 mm
0.1260
3.2000
#30
0.1285
3.2639
3.3 mm
0.1299
3.3000
3.4 mm
0.1339
3.4000
#29
0.1360
3.4544
3.5 mm
0.1378
3.5000
#28
0.1405
3.5687
9/64 in
0.1406
3.5719
3.6 mm
0.1417
3.6000
#27
0.1440
3.6576
3.7 mm
0.1457
3.7000
#26
0.1470
3.7338
#25
0.1495
3.7973
3.8 mm
0.1496
3.8000
#24
0.1520
3.8608
3.9 mm
0.1535
3.9000
#23
0.1540
3.9116
5/32 in
0.1563
3.9688
#22
0.1570
3.9878
4 mm
0.1575
4.0000
#21
0.1590
4.0386
#20
0.1610
4.0894
4.1 mm
0.1614
4.1000
4.2 mm
0.1654
4.2000
#19
0.1660
4.2164
4.3 mm
0.1693
4.3000
#18
0.1695
4.3053
11/64 in
0.1719
4.3656
#17
0.1730
4.3942
4.4 mm
0.1732
4.4000
#16
0.1770
4.4958
4.5 mm
0.1772
4.5000
#15
0.1800
4.5720
4.6 mm
0.1811
4.6000
#14
0.1820
4.6228
#13
0.1850
4.6990
4.7 mm
0.1850
4.7000
3/16 in
0.1875
4.7625
4.8 mm
0.1890
4.8000
#12
0.1890
4.8006
#11
0.1910
4.8514
4.9 mm
0.1929
4.9000
#10
0.1935
4.9149
#9
0.1960
4.9784
5 mm
0.1969
5.0000
#8
0.1990
5.0546
5.1 mm
0.2008
5.1000
#7
0.2010
5.1054
13/64 in
0.2031
5.1594
#6
0.2040
5.1816
5.2 mm
0.2047
5.2000
#5
0.2055
5.2197
5.3 mm
0.2087
5.3000
#4
0.2090
5.3086
5.4 mm
0.2126
5.4000
#3
0.2130
5.4102
5.5 mm
0.2165
5.5000
7/32 in
0.2188
5.5563
5.6 mm
0.2205
5.6000
#2
0.2210
5.6134
5.7 mm
0.2244
5.7000
#1
0.2280
5.7912
5.8 mm
0.2284
5.8000
5.9 mm
0.2323
5.9000
A
0.2340
5.9436
15/64 in
0.2344
5.9531
6 mm
0.2362
6.0000
B
0.2380
6.0452
6.1 mm
0.2402
6.1000
C
0.2420
6.1468
6.2 mm
0.2441
6.2000
D
0.2460
6.2484
6.3 mm
0.2480
6.3000
1/4 in
0.2500
6.3500
E
0.2500
6.3500
6.4 mm
0.2520
6.4000
6.5 mm
0.2559
6.5000
F
0.2570
6.5278
6.6 mm
0.2598
6.6000
G
0.2610
6.6294
6.7 mm
0.2638
6.7000
17/64 in
0.2656
6.7469
H
0.2660
6.7564
6.8 mm
0.2677
6.8000
6.9 mm
0.2717
6.9000
I
0.2720
6.9088
7 mm
0.2756
7.0000
J
0.2770
7.0358
7.1 mm
0.2795
7.1000
K
0.2810
7.1374
9/32 in
0.2813
7.1438
7.2 mm
0.2835
7.2000
7.3 mm
0.2874
7.3000
L
0.2900
7.3660
7.4 mm
0.2913
7.4000
M
0.2950
7.4930
7.5 mm
0.2953
7.5000
19/64 in
0.2969
7.5406
7.6 mm
0.2992
7.6000
N
0.3020
7.6708
7.7 mm
0.3032
7.7000
7.8 mm
0.3071
7.8000
7.9 mm
0.3110
7.9000
5/16 in
0.3125
7.9375
8 mm
0.3150
8.0000
O
0.3160
8.0264
8.1 mm
0.3189
8.1000
8.2 mm
0.3228
8.2000
P
0.3230
8.2042
8.3 mm
0.3268
8.3000
21/64 in
0.3281
8.3344
8.4 mm
0.3307
8.4000
Q
0.3320
8.4328
8.5 mm
0.3347
8.5000
8.6 mm
0.3386
8.6000
R
0.3390
8.6106
8.7 mm
0.3425
8.7000
11/32 in
0.3438
8.7313
8.8 mm
0.3465
8.8000
S
0.3480
8.8392
8.9 mm
0.3504
8.9000
9 mm
0.3543
9.0000
T
0.3580
9.0932
9.1 mm
0.3583
9.1000
23/64 in
0.3594
9.1281
9.2 mm
0.3622
9.2000
9.3 mm
0.3661
9.3000
U
0.3680
9.3472
9.4 mm
0.3701
9.4000
9.5 mm
0.3740
9.5000
3/8 in
0.3750
9.5250
V
0.3770
9.5758
9.6 mm
0.3780
9.6000
9.7 mm
0.3819
9.7000
9.8 mm
0.3858
9.8000
W
0.3860
9.8044
9.9 mm
0.3898
9.9000
25/64 in
0.3906
9.9219
10 mm
0.3937
10.0000
X
0.3970
10.0838
Y
0.4040
10.2616
13/32 in
0.4063
10.3188
Z
0.4130
10.4902
10.5 mm
0.4134
10.5000
27/64 in
0.4219
10.7156
11 mm
0.4331
11.0000
7/16 in
0.4375
11.1125
11.5 mm
0.4528
11.5000
29/64 in
0.4531
11.5094
15/32 in
0.4688
11.9063
12 mm
0.4724
12.0000
31/64 in
0.4844
12.3031
12.5 mm
0.4921
12.5000
1/2 in
0.5000
12.7000
13 mm
0.5118
13.0000
33/64 in
0.5156
13.0969
17/32 in
0.5313
13.4938
13.5 mm
0.5315
13.5000
35/64 in
0.5469
13.8906
14 mm
0.5512
14.0000
9/16 in
0.5625
14.2875
14.5 mm
0.5709
14.5000
37/64 in
0.5781
14.6844
15 mm
0.5906
15.0000
19/32 in
0.5938
15.0813
39/64 in
0.6094
15.4781
15.5 mm
0.6102
15.5000
5/8 in
0.6250
15.8750
16 mm
0.6299
16.0000
41/64 in
0.6406
16.2719
16.5 mm
0.6496
16.5000
17 mm
0.6693
17.0000
43/64 in
0.6719
17.0656
11/16 in
0.6875
17.4625
17.5 mm
0.6890
17.5000
45/64 in
0.7031
17.8594
18 mm
0.7087
18.0000
23/32 in
0.7188
18.2563
18.5 mm
0.7284
18.5000
47/64 in
0.7344
18.6531
19 mm
0.7480
19.0000
3/4 in
0.7500
19.0500
49/64 in
0.7656
19.4469
19.5 mm
0.7677
19.5000
25/32 in
0.7813
19.8438
20 mm
0.7874
20.0000
51/64 in
0.7969
20.2406
20.5 mm
0.8071
20.5000
13/16 in
0.8125
20.6375
21 mm
0.8268
21.0000
53/64 in
0.8281
21.0344
27/32 in
0.8438
21.4313
21.5 mm
0.8465
21.5000
55/64 in
0.8594
21.8281
22 mm
0.8661
22.0000
7/8 in
0.8750
22.2250
22.5 mm
0.8858
22.5000
57/64 in
0.8906
22.6219
23 mm
0.9055
23.0000
29/32 in
0.9063
23.0188
21/23 in
0.9130
23.1913
59/64 in
0.9219
23.4156
23.5 mm
0.9252
23.5000
15/16 in
0.9375
23.8125
24 mm
0.9449
24.0000
61/64 in
0.9531
24.2094
24.5 mm
0.9646
24.5000
31/32 in
0.9688
24.6063
25 mm
0.9843
25.0000
63/64 in
0.9844
25.0031
1 in
1.0000
25.4000
25.5 mm
1.0039
25.5000
1 1/64 in
1.0156
25.7969
26 mm
1.0236
26.0000
1 1/32 in
1.0313
26.1938
26.5 mm
1.0433
26.5000
1 3/64 in
1.0469
26.5906
1 1/16 in
1.0625
26.9875
27 mm
1.0630
27.0000
1 5/64 in
1.0781
27.3844
27.5 mm
1.0827
27.5000
1 3/32 in
1.0938
27.7813
28 mm
1.1024
28.0000
1 7/64 in
1.1094
28.1781
28.5 mm
1.1221
28.5000
1 1/8 in
1.1250
28.5750
1 9/64 in
1.1406
28.9719
29 mm
1.1417
29.0000
1 5/32 in
1.1563
29.3688
29.5 mm
1.1614
29.5000
1 11/64 in
1.1719
29.7656
30 mm
1.1811
30.0000
1 3/16 in
1.1875
30.1625
30.5 mm
1.2008
30.5000
1 13/64 in
1.2031
30.5594
1 7/32 in
1.2188
30.9563
31 mm
1.2205
31.0000
1 15/64 in
1.2344
31.3531
31.5 mm
1.2402
31.5000
1 1/4 in
1.2500
31.7500
32 mm
1.2598
32.0000
1 17/64 in
1.2656
32.1469
32.5 mm
1.2795
32.5000
1 9/32 in
1.2813
32.5438
1 19/64 in
1.2969
32.9406
33 mm
1.2992
33.0000
1 5/16 in
1.3125
33.3375
33.5 mm
1.3189
33.5000
1 21/64 in
1.3281
33.7344
34 mm
1.3386
34.0000
1 11/32 in
1.3438
34.1313
34.5 mm
1.3583
34.5000
1 23/64 in
1.3594
34.5281
1 3/8 in
1.3750
34.9250
35 mm
1.3780
35.0000
1 25/64 in
1.3906
35.3219
35.5 mm
1.3976
35.5000
1 13/32 in
1.4063
35.7188
36 mm
1.4173
36.0000
1 27/64 in
1.4219
36.1156
36.5 mm
1.4370
36.5000
1 7/16 in
1.4375
36.5125
1 29/64 in
1.4531
36.9094
37 mm
1.4567
37.0000
1 15/32 in
1.4688
37.3063
37.5 mm
1.4764
37.5000
1 31/64 in
1.4844
37.7031
38 mm
1.4961
38.0000
1 1/2 in
1.5000
38.1000

Affiliate Partners

Help support us by using our affiliate links below.

Amazon.com affiliate link
Amazon.co.uk affiliate link
Ebay.co.uk affiliate link

Social Links