Standard Drill Sizes Table

A complete reference of drill bit sizes across metric, fractional inch, letter, and number systems. Handy for specifying holes, selecting tap drills, and programming CNC tool lists.

Drill size	Diameter (in)	Diameter (mm)
No.107	0.0019	0.048
0.05 mm	0.0020	0.050
No.106	0.0023	0.058
No.105	0.0027	0.069
No.104	0.0031	0.079
No.103	0.0035	0.089
No.102	0.0039	0.099
0.1 mm	0.0039	0.100
No.101	0.0043	0.109
No.100	0.0047	0.119
No.99	0.0051	0.130
No.98	0.0055	0.140
No.97	0.0059	0.150
No.96	0.0063	0.160
No.95	0.0067	0.170
No.94	0.0071	0.180
No.93	0.0075	0.191
0.2 mm	0.0079	0.200
No.92	0.0079	0.201
No.91	0.0083	0.211
No.90	0.0087	0.221
No.89	0.0091	0.231
No.88	0.0095	0.241
No.87	0.0100	0.254
No.86	0.0105	0.267
No.85	0.0110	0.279
No.84	0.0115	0.292
0.3 mm	0.0118	0.300
No.83	0.0120	0.305
No.82	0.0125	0.318
No.81	0.0130	0.330
No.80	0.0135	0.343
No.79	0.0145	0.368
1/64 in	0.0156	0.397
0.4 mm	0.0158	0.400
No.78	0.0160	0.406
No.77	0.0180	0.457
0.5 mm	0.0197	0.500
No.76	0.0200	0.508
No.75	0.0210	0.533
No.74	0.0225	0.572
0.6 mm	0.0236	0.600
No.73	0.0240	0.610
No.72	0.0250	0.635
No.71	0.0260	0.660
0.7 mm	0.0276	0.700
No.70	0.0280	0.711
No.69	0.0292	0.742
No.68	0.0310	0.787
1/32 in	0.0313	0.794
0.8 mm	0.0315	0.800
No.67	0.0320	0.813
No.66	0.0330	0.838
No.65	0.0350	0.889
0.9 mm	0.0354	0.900
No.64	0.0360	0.914
No.63	0.0370	0.940
No.62	0.0380	0.965
No.61	0.0390	0.991
1 mm	0.0394	1.000
No.60	0.0400	1.016
No.59	0.0410	1.041
No.58	0.0420	1.067
No.57	0.0430	1.092
1.1 mm	0.0433	1.100
No.56	0.0465	1.181
3/64 in	0.0469	1.191
1.2 mm	0.0472	1.200
1.3 mm	0.0512	1.300
No.55	0.0520	1.321
No.54	0.0550	1.397
1.4 mm	0.0551	1.400
1.5 mm	0.0591	1.500
No.53	0.0595	1.511
1/16 in	0.0625	1.587
1.6 mm	0.0630	1.600
No.52	0.0635	1.613
1.7 mm	0.0669	1.700
No.51	0.0670	1.702
No.50	0.0700	1.778
1.8 mm	0.0709	1.800
No.49	0.0730	1.854
1.9 mm	0.0748	1.900
No.48	0.0760	1.930
5/64 in	0.0781	1.984
No.47	0.0785	1.994
2 mm	0.0787	2.000
No.46	0.0810	2.057
No.45	0.0820	2.083
2.1 mm	0.0827	2.100
No.44	0.0860	2.184
2.2 mm	0.0866	2.200
No.43	0.0890	2.261
2.3 mm	0.0906	2.300
No.42	0.0935	2.375
3/32 in	0.0938	2.381
2.4 mm	0.0945	2.400
No.41	0.0960	2.438
No.40	0.0980	2.489
2.5 mm	0.0984	2.500
No.39	0.0995	2.527
No.38	0.1015	2.578
2.6 mm	0.1024	2.600
No.37	0.1040	2.642
2.7 mm	0.1063	2.700
No.36	0.1065	2.705
7/64 in	0.1094	2.778
No.35	0.1100	2.794
2.8 mm	0.1102	2.800
No.34	0.1110	2.819
No.33	0.1130	2.870
2.9 mm	0.1142	2.900
No.32	0.1160	2.946
3 mm	0.1181	3.000
No.31	0.1200	3.048
3.1 mm	0.1221	3.100
1/8 in	0.1250	3.175
3.2 mm	0.1260	3.200
No.30	0.1285	3.264
3.3 mm	0.1299	3.300
3.4 mm	0.1339	3.400
No.29	0.1360	3.454
3.5 mm	0.1378	3.500
No.28	0.1405	3.569
9/64 in	0.1406	3.572
3.6 mm	0.1417	3.600
No.27	0.1440	3.658
3.7 mm	0.1457	3.700
No.26	0.1470	3.734
No.25	0.1495	3.797
3.8 mm	0.1496	3.800
No.24	0.1520	3.861
3.9 mm	0.1535	3.900
No.23	0.1540	3.912
5/32 in	0.1563	3.969
No.22	0.1570	3.988
4 mm	0.1575	4.000
No.21	0.1590	4.039
No.20	0.1610	4.089
4.1 mm	0.1614	4.100
4.2 mm	0.1654	4.200
No.19	0.1660	4.216
4.3 mm	0.1693	4.300
No.18	0.1695	4.305
11/64 in	0.1719	4.366
No.17	0.1730	4.394
4.4 mm	0.1732	4.400
No.16	0.1770	4.496
4.5 mm	0.1772	4.500
No.15	0.1800	4.572
4.6 mm	0.1811	4.600
No.14	0.1820	4.623
No.13	0.1850	4.699
4.7 mm	0.1850	4.700
3/16 in	0.1875	4.763
4.8 mm	0.1890	4.800
No.12	0.1890	4.801
No.11	0.1910	4.851
4.9 mm	0.1929	4.900
No.10	0.1935	4.915
No.9	0.1960	4.978
5 mm	0.1969	5.000
No.8	0.1990	5.055
5.1 mm	0.2008	5.100
No.7	0.2010	5.105
13/64 in	0.2031	5.159
No.6	0.2040	5.182
5.2 mm	0.2047	5.200
No.5	0.2055	5.220
5.3 mm	0.2087	5.300
No.4	0.2090	5.309
5.4 mm	0.2126	5.400
No.3	0.2130	5.410
5.5 mm	0.2165	5.500
7/32 in	0.2188	5.556
5.6 mm	0.2205	5.600
No.2	0.2210	5.613
5.7 mm	0.2244	5.700
No.1	0.2280	5.791
5.8 mm	0.2284	5.800
5.9 mm	0.2323	5.900
A	0.2340	5.944
15/64 in	0.2344	5.953
6 mm	0.2362	6.000
B	0.2380	6.045
6.1 mm	0.2402	6.100
C	0.2420	6.147
6.2 mm	0.2441	6.200
D	0.2460	6.248
6.3 mm	0.2480	6.300
1/4 in	0.2500	6.350
E	0.2500	6.350
6.4 mm	0.2520	6.400
6.5 mm	0.2559	6.500
F	0.2570	6.528
6.6 mm	0.2598	6.600
G	0.2610	6.629
6.7 mm	0.2638	6.700
17/64 in	0.2656	6.747
H	0.2660	6.756
6.8 mm	0.2677	6.800
6.9 mm	0.2717	6.900
I	0.2720	6.909
7 mm	0.2756	7.000
J	0.2770	7.036
7.1 mm	0.2795	7.100
K	0.2810	7.137
9/32 in	0.2813	7.144
7.2 mm	0.2835	7.200
7.3 mm	0.2874	7.300
L	0.2900	7.366
7.4 mm	0.2913	7.400
M	0.2950	7.493
7.5 mm	0.2953	7.500
19/64 in	0.2969	7.541
7.6 mm	0.2992	7.600
N	0.3020	7.671
7.7 mm	0.3032	7.700
7.8 mm	0.3071	7.800
7.9 mm	0.3110	7.900
5/16 in	0.3125	7.938
8 mm	0.3150	8.000
O	0.3160	8.026
8.1 mm	0.3189	8.100
8.2 mm	0.3228	8.200
P	0.3230	8.204
8.3 mm	0.3268	8.300
21/64 in	0.3281	8.334
8.4 mm	0.3307	8.400
Q	0.3320	8.433
8.5 mm	0.3347	8.500
8.6 mm	0.3386	8.600
R	0.3390	8.611
8.7 mm	0.3425	8.700
11/32 in	0.3438	8.731
8.8 mm	0.3465	8.800
S	0.3480	8.839
8.9 mm	0.3504	8.900
9 mm	0.3543	9.000
T	0.3580	9.093
9.1 mm	0.3583	9.100
23/64 in	0.3594	9.128
9.2 mm	0.3622	9.200
9.3 mm	0.3661	9.300
U	0.3680	9.347
9.4 mm	0.3701	9.400
9.5 mm	0.3740	9.500
3/8 in	0.3750	9.525
V	0.3770	9.576
9.6 mm	0.3780	9.600
9.7 mm	0.3819	9.700
9.8 mm	0.3858	9.800
W	0.3860	9.804
9.9 mm	0.3898	9.900
25/64 in	0.3906	9.922
10 mm	0.3937	10.000
X	0.3970	10.084
Y	0.4040	10.262
13/32 in	0.4063	10.319
Z	0.4130	10.490
10.5 mm	0.4134	10.500
27/64 in	0.4219	10.716
11 mm	0.4331	11.000
7/16 in	0.4375	11.113
11.5 mm	0.4528	11.500
29/64 in	0.4531	11.509
15/32 in	0.4688	11.906
12 mm	0.4724	12.000
31/64 in	0.4844	12.303
12.5 mm	0.4921	12.500
1/2 in	0.5000	12.700
13 mm	0.5118	13.000
33/64 in	0.5156	13.097
17/32 in	0.5313	13.494
13.5 mm	0.5315	13.500
35/64 in	0.5469	13.891
14 mm	0.5512	14.000
9/16 in	0.5625	14.287
14.5 mm	0.5709	14.500
37/64 in	0.5781	14.684
15 mm	0.5906	15.000
19/32 in	0.5938	15.081
39/64 in	0.6094	15.478
15.5 mm	0.6102	15.500
5/8 in	0.6250	15.875
16 mm	0.6299	16.000
41/64 in	0.6406	16.272
16.5 mm	0.6496	16.500
17 mm	0.6693	17.000
43/64 in	0.6719	17.066
11/16 in	0.6875	17.462
17.5 mm	0.6890	17.500
45/64 in	0.7031	17.859
18 mm	0.7087	18.000
23/32 in	0.7188	18.256
18.5 mm	0.7284	18.500
47/64 in	0.7344	18.653
19 mm	0.7480	19.000
3/4 in	0.7500	19.050
49/64 in	0.7656	19.447
19.5 mm	0.7677	19.500
25/32 in	0.7813	19.844
20 mm	0.7874	20.000
51/64 in	0.7969	20.241
20.5 mm	0.8071	20.500
13/16 in	0.8125	20.637
21 mm	0.8268	21.000
53/64 in	0.8281	21.034
27/32 in	0.8438	21.431
21.5 mm	0.8465	21.500
55/64 in	0.8594	21.828
22 mm	0.8661	22.000
7/8 in	0.8750	22.225
22.5 mm	0.8858	22.500
57/64 in	0.8906	22.622
23 mm	0.9055	23.000
29/32 in	0.9063	23.019
21/23 in	0.9130	23.191
59/64 in	0.9219	23.416
23.5 mm	0.9252	23.500
15/16 in	0.9375	23.812
24 mm	0.9449	24.000
61/64 in	0.9531	24.209
24.5 mm	0.9646	24.500
31/32 in	0.9688	24.606
25 mm	0.9843	25.000
63/64 in	0.9844	25.003
1 in	1.0000	25.400
25.5 mm	1.0039	25.500
1 1/64 in	1.0156	25.797
26 mm	1.0236	26.000
1 1/32 in	1.0313	26.194
26.5 mm	1.0433	26.500
1 3/64 in	1.0469	26.591
1 1/16 in	1.0625	26.988
27 mm	1.0630	27.000
1 5/64 in	1.0781	27.384
27.5 mm	1.0827	27.500
1 3/32 in	1.0938	27.781
28 mm	1.1024	28.000
1 7/64 in	1.1094	28.178
28.5 mm	1.1221	28.500
1 1/8 in	1.1250	28.575
1 9/64 in	1.1406	28.972
29 mm	1.1417	29.000
1 5/32 in	1.1563	29.369
29.5 mm	1.1614	29.500
1 11/64 in	1.1719	29.766
30 mm	1.1811	30.000
1 3/16 in	1.1875	30.163
30.5 mm	1.2008	30.500
1 13/64 in	1.2031	30.559
1 7/32 in	1.2188	30.956
31 mm	1.2205	31.000
1 15/64 in	1.2344	31.353
31.5 mm	1.2402	31.500
1 1/4 in	1.2500	31.750
32 mm	1.2598	32.000
1 17/64 in	1.2656	32.147
32.5 mm	1.2795	32.500
1 9/32 in	1.2813	32.544
1 19/64 in	1.2969	32.941
33 mm	1.2992	33.000
1 5/16 in	1.3125	33.337
33.5 mm	1.3189	33.500
1 21/64 in	1.3281	33.734
34 mm	1.3386	34.000
1 11/32 in	1.3438	34.131
34.5 mm	1.3583	34.500
1 23/64 in	1.3594	34.528
1 3/8 in	1.3750	34.925
35 mm	1.3780	35.000
1 25/64 in	1.3906	35.322
35.5 mm	1.3976	35.500
1 13/32 in	1.4063	35.719
36 mm	1.4173	36.000
1 27/64 in	1.4219	36.116
36.5 mm	1.4370	36.500
1 7/16 in	1.4375	36.513
1 29/64 in	1.4531	36.909
37 mm	1.4567	37.000
1 15/32 in	1.4688	37.306
37.5 mm	1.4764	37.500
1 31/64 in	1.4844	37.703
38 mm	1.4961	38.000
1 1/2 in	1.5000	38.100