What metric drill is closest to 1/4 in?

6.35 mm is exact; the nearest standard metric drill is 6.4 mm.

What is a #7 drill in mm?

5.105 mm (0.201 in), the 1/4-20 tap drill.

Inch and metric drill chart

Every common drill, inch and metric, in one list sorted by size, so you can see which metric drill sits next to a letter or number drill. Use the drill finder to jump to the nearest size.

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Fractional, number, letter and metric drills by size
Drill	Type	Inch	mm
0.1 mm	metric	0.0039	0.100
#97	number	0.0059	0.150
0.15 mm	metric	0.0059	0.150
#96	number	0.0063	0.160
#95	number	0.0067	0.170
#94	number	0.0071	0.180
#93	number	0.0075	0.190
0.2 mm	metric	0.0079	0.200
#92	number	0.0079	0.201
#91	number	0.0083	0.211
#90	number	0.0087	0.221
#89	number	0.0091	0.231
#88	number	0.0095	0.241
0.25 mm	metric	0.0098	0.250
#87	number	0.0100	0.254
#86	number	0.0105	0.267
#85	number	0.0110	0.279
#84	number	0.0115	0.292
0.3 mm	metric	0.0118	0.300
#83	number	0.0120	0.305
#82	number	0.0125	0.318
#81	number	0.0130	0.330
#80	number	0.0135	0.343
0.35 mm	metric	0.0138	0.350
#79	number	0.0145	0.368
1/64	fraction	0.0156	0.397
0.4 mm	metric	0.0158	0.400
#78	number	0.0160	0.406
0.45 mm	metric	0.0177	0.450
#77	number	0.0180	0.457
0.5 mm	metric	0.0197	0.500
#76	number	0.0200	0.508
#75	number	0.0210	0.533
0.55 mm	metric	0.0216	0.550
#74	number	0.0225	0.571
0.6 mm	metric	0.0236	0.600
#73	number	0.0240	0.610
#72	number	0.0250	0.635
0.65 mm	metric	0.0256	0.650
#71	number	0.0260	0.660
0.7 mm	metric	0.0276	0.700
#70	number	0.0280	0.711
#69	number	0.0292	0.742
0.75 mm	metric	0.0295	0.750
#68	number	0.0310	0.787
1/32	fraction	0.0313	0.794
0.8 mm	metric	0.0315	0.800
#67	number	0.0320	0.813
#66	number	0.0330	0.838
0.85 mm	metric	0.0335	0.850
#65	number	0.0350	0.889
0.9 mm	metric	0.0354	0.900
#64	number	0.0360	0.914
#63	number	0.0370	0.940
0.95 mm	metric	0.0374	0.950
#62	number	0.0380	0.965
#61	number	0.0390	0.991
1.0 mm	metric	0.0394	1.000
#60	number	0.0400	1.016
#59	number	0.0410	1.041
1.05 mm	metric	0.0413	1.050
#58	number	0.0420	1.067
#57	number	0.0430	1.092
1.1 mm	metric	0.0433	1.100
1.15 mm	metric	0.0453	1.150
#56	number	0.0465	1.181
3/64	fraction	0.0469	1.191
1.2 mm	metric	0.0472	1.200
1.25 mm	metric	0.0492	1.250
1.3 mm	metric	0.0512	1.300
#55	number	0.0520	1.321
1.35 mm	metric	0.0532	1.350
#54	number	0.0550	1.397
1.4 mm	metric	0.0551	1.400
1.45 mm	metric	0.0571	1.450
1.5 mm	metric	0.0591	1.500
#53	number	0.0595	1.511
1.55 mm	metric	0.0610	1.550
1/16	fraction	0.0625	1.588
1.6 mm	metric	0.0630	1.600
#52	number	0.0635	1.613
1.65 mm	metric	0.0650	1.650
1.7 mm	metric	0.0669	1.700
#51	number	0.0670	1.702
1.75 mm	metric	0.0689	1.750
#50	number	0.0700	1.778
1.8 mm	metric	0.0709	1.800
1.85 mm	metric	0.0728	1.850
#49	number	0.0730	1.854
1.9 mm	metric	0.0748	1.900
#48	number	0.0760	1.930
1.95 mm	metric	0.0768	1.950
5/64	fraction	0.0781	1.984
#47	number	0.0785	1.994
2.0 mm	metric	0.0787	2.000
2.05 mm	metric	0.0807	2.050
#46	number	0.0810	2.057
#45	number	0.0820	2.083
2.1 mm	metric	0.0827	2.100
2.15 mm	metric	0.0847	2.150
#44	number	0.0860	2.184
2.2 mm	metric	0.0866	2.200
2.25 mm	metric	0.0886	2.250
#43	number	0.0890	2.261
2.3 mm	metric	0.0906	2.300
2.35 mm	metric	0.0925	2.350
#42	number	0.0935	2.375
3/32	fraction	0.0938	2.381
2.4 mm	metric	0.0945	2.400
#41	number	0.0960	2.438
2.45 mm	metric	0.0965	2.450
#40	number	0.0980	2.489
2.5 mm	metric	0.0984	2.500
#39	number	0.0995	2.527
2.55 mm	metric	0.1004	2.550
#38	number	0.1015	2.578
2.6 mm	metric	0.1024	2.600
#37	number	0.1040	2.642
2.65 mm	metric	0.1043	2.650
2.7 mm	metric	0.1063	2.700
#36	number	0.1065	2.705
2.75 mm	metric	0.1083	2.750
7/64	fraction	0.1094	2.778
#35	number	0.1100	2.794
2.8 mm	metric	0.1102	2.800
#34	number	0.1110	2.819
2.85 mm	metric	0.1122	2.850
#33	number	0.1130	2.870
2.9 mm	metric	0.1142	2.900
#32	number	0.1160	2.946
2.95 mm	metric	0.1161	2.950
3.0 mm	metric	0.1181	3.000
#31	number	0.1200	3.048
3.1 mm	metric	0.1221	3.100
1/8	fraction	0.1250	3.175
3.2 mm	metric	0.1260	3.200
#30	number	0.1285	3.264
3.3 mm	metric	0.1299	3.300
3.4 mm	metric	0.1339	3.400
#29	number	0.1360	3.454
3.5 mm	metric	0.1378	3.500
#28	number	0.1405	3.569
9/64	fraction	0.1406	3.572
3.6 mm	metric	0.1417	3.600
#27	number	0.1440	3.658
3.7 mm	metric	0.1457	3.700
#26	number	0.1470	3.734
#25	number	0.1495	3.797
3.8 mm	metric	0.1496	3.800
#24	number	0.1520	3.861
3.9 mm	metric	0.1535	3.900
#23	number	0.1540	3.912
5/32	fraction	0.1563	3.969
#22	number	0.1570	3.988
4.0 mm	metric	0.1575	4.000
#21	number	0.1590	4.039
#20	number	0.1610	4.089
4.1 mm	metric	0.1614	4.100
4.2 mm	metric	0.1653	4.200
#19	number	0.1660	4.216
4.3 mm	metric	0.1693	4.300
#18	number	0.1695	4.305
11/64	fraction	0.1719	4.366
#17	number	0.1730	4.394
4.4 mm	metric	0.1732	4.400
#16	number	0.1770	4.496
4.5 mm	metric	0.1772	4.500
#15	number	0.1800	4.572
4.6 mm	metric	0.1811	4.600
#14	number	0.1820	4.623
#13	number	0.1850	4.699
4.7 mm	metric	0.1850	4.700
3/16	fraction	0.1875	4.762
4.8 mm	metric	0.1890	4.800
#12	number	0.1890	4.801
#11	number	0.1910	4.851
4.9 mm	metric	0.1929	4.900
#10	number	0.1935	4.915
#9	number	0.1960	4.978
5.0 mm	metric	0.1968	5.000
#8	number	0.1990	5.055
5.1 mm	metric	0.2008	5.100
#7	number	0.2010	5.105
13/64	fraction	0.2031	5.159
#6	number	0.2040	5.182
5.2 mm	metric	0.2047	5.200
#5	number	0.2055	5.220
5.3 mm	metric	0.2087	5.300
#4	number	0.2090	5.309
5.4 mm	metric	0.2126	5.400
#3	number	0.2130	5.410
5.5 mm	metric	0.2165	5.500
7/32	fraction	0.2188	5.556
5.6 mm	metric	0.2205	5.600
#2	number	0.2210	5.613
5.7 mm	metric	0.2244	5.700
#1	number	0.2280	5.791
5.8 mm	metric	0.2283	5.800
5.9 mm	metric	0.2323	5.900
A	letter	0.2340	5.944
15/64	fraction	0.2344	5.953
6.0 mm	metric	0.2362	6.000
B	letter	0.2380	6.045
6.1 mm	metric	0.2402	6.100
C	letter	0.2420	6.147
6.2 mm	metric	0.2441	6.200
D	letter	0.2460	6.248
6.3 mm	metric	0.2480	6.300
1/4	fraction	0.2500	6.350
E	letter	0.2500	6.350
6.4 mm	metric	0.2520	6.400
6.5 mm	metric	0.2559	6.500
F	letter	0.2570	6.528
6.6 mm	metric	0.2598	6.600
G	letter	0.2610	6.629
6.7 mm	metric	0.2638	6.700
17/64	fraction	0.2656	6.747
H	letter	0.2660	6.756
6.8 mm	metric	0.2677	6.800
6.9 mm	metric	0.2717	6.900
I	letter	0.2720	6.909
7.0 mm	metric	0.2756	7.000
J	letter	0.2770	7.036
7.1 mm	metric	0.2795	7.100
K	letter	0.2810	7.137
9/32	fraction	0.2813	7.144
7.2 mm	metric	0.2835	7.200
7.3 mm	metric	0.2874	7.300
L	letter	0.2900	7.366
7.4 mm	metric	0.2913	7.400
M	letter	0.2950	7.493
7.5 mm	metric	0.2953	7.500
19/64	fraction	0.2969	7.541
7.6 mm	metric	0.2992	7.600
N	letter	0.3020	7.671
7.7 mm	metric	0.3031	7.700
7.8 mm	metric	0.3071	7.800
7.9 mm	metric	0.3110	7.900
5/16	fraction	0.3125	7.938
8.0 mm	metric	0.3150	8.000
O	letter	0.3160	8.026
8.1 mm	metric	0.3189	8.100
8.2 mm	metric	0.3228	8.200
P	letter	0.3230	8.204
8.3 mm	metric	0.3268	8.300
21/64	fraction	0.3281	8.334
8.4 mm	metric	0.3307	8.400
Q	letter	0.3320	8.433
8.5 mm	metric	0.3347	8.500
8.6 mm	metric	0.3386	8.600
R	letter	0.3390	8.611
8.7 mm	metric	0.3425	8.700
11/32	fraction	0.3438	8.731
8.8 mm	metric	0.3465	8.800
S	letter	0.3480	8.839
8.9 mm	metric	0.3504	8.900
9.0 mm	metric	0.3543	9.000
T	letter	0.3580	9.093
9.1 mm	metric	0.3583	9.100
23/64	fraction	0.3594	9.128
9.2 mm	metric	0.3622	9.200
9.3 mm	metric	0.3661	9.300
U	letter	0.3680	9.347
9.4 mm	metric	0.3701	9.400
9.5 mm	metric	0.3740	9.500
3/8	fraction	0.3750	9.525
V	letter	0.3770	9.576
9.6 mm	metric	0.3780	9.600
9.7 mm	metric	0.3819	9.700
9.8 mm	metric	0.3858	9.800
W	letter	0.3860	9.804
9.9 mm	metric	0.3898	9.900
25/64	fraction	0.3906	9.922
10.0 mm	metric	0.3937	10.000
X	letter	0.3970	10.084
10.1 mm	metric	0.3976	10.100
10.2 mm	metric	0.4016	10.200
Y	letter	0.4040	10.262
10.3 mm	metric	0.4055	10.300
13/32	fraction	0.4063	10.319
10.4 mm	metric	0.4094	10.400
Z	letter	0.4130	10.490
10.5 mm	metric	0.4134	10.500
10.6 mm	metric	0.4173	10.600
10.7 mm	metric	0.4213	10.700
27/64	fraction	0.4219	10.716
10.8 mm	metric	0.4252	10.800
10.9 mm	metric	0.4291	10.900
11.0 mm	metric	0.4331	11.000
11.1 mm	metric	0.4370	11.100
7/16	fraction	0.4375	11.112
11.2 mm	metric	0.4409	11.200
11.3 mm	metric	0.4449	11.300
11.4 mm	metric	0.4488	11.400
11.5 mm	metric	0.4528	11.500
29/64	fraction	0.4531	11.509
11.6 mm	metric	0.4567	11.600
11.7 mm	metric	0.4606	11.700
11.8 mm	metric	0.4646	11.800
11.9 mm	metric	0.4685	11.900
15/32	fraction	0.4688	11.906
12.0 mm	metric	0.4724	12.000
12.1 mm	metric	0.4764	12.100
12.2 mm	metric	0.4803	12.200
12.3 mm	metric	0.4843	12.300
31/64	fraction	0.4844	12.303
12.4 mm	metric	0.4882	12.400
12.5 mm	metric	0.4921	12.500
12.6 mm	metric	0.4961	12.600
1/2	fraction	0.5000	12.700
12.7 mm	metric	0.5000	12.700
12.8 mm	metric	0.5039	12.800
12.9 mm	metric	0.5079	12.900
13.0 mm	metric	0.5118	13.000
33/64	fraction	0.5156	13.097
13.1 mm	metric	0.5158	13.100
13.2 mm	metric	0.5197	13.200
13.3 mm	metric	0.5236	13.300
13.4 mm	metric	0.5276	13.400
17/32	fraction	0.5313	13.494
13.5 mm	metric	0.5315	13.500
13.6 mm	metric	0.5354	13.600
13.7 mm	metric	0.5394	13.700
13.8 mm	metric	0.5433	13.800
35/64	fraction	0.5469	13.891
13.9 mm	metric	0.5472	13.900
14.0 mm	metric	0.5512	14.000
14.25 mm	metric	0.5610	14.250
9/16	fraction	0.5625	14.288
14.5 mm	metric	0.5709	14.500
37/64	fraction	0.5781	14.684
14.75 mm	metric	0.5807	14.750
15.0 mm	metric	0.5906	15.000
19/32	fraction	0.5938	15.081
15.25 mm	metric	0.6004	15.250
39/64	fraction	0.6094	15.478
15.5 mm	metric	0.6102	15.500
15.75 mm	metric	0.6201	15.750
5/8	fraction	0.6250	15.875
16.0 mm	metric	0.6299	16.000
16.25 mm	metric	0.6398	16.250
41/64	fraction	0.6406	16.272
16.5 mm	metric	0.6496	16.500
21/32	fraction	0.6563	16.669
16.75 mm	metric	0.6594	16.750
17.0 mm	metric	0.6693	17.000
43/64	fraction	0.6719	17.066
17.25 mm	metric	0.6791	17.250
11/16	fraction	0.6875	17.463
17.5 mm	metric	0.6890	17.500
17.75 mm	metric	0.6988	17.750
45/64	fraction	0.7031	17.859
18.0 mm	metric	0.7087	18.000
18.25 mm	metric	0.7185	18.250
23/32	fraction	0.7188	18.256
18.5 mm	metric	0.7284	18.500
47/64	fraction	0.7344	18.653
18.75 mm	metric	0.7382	18.750
19.0 mm	metric	0.7480	19.000
3/4	fraction	0.7500	19.050
19.25 mm	metric	0.7579	19.250
49/64	fraction	0.7656	19.447
19.5 mm	metric	0.7677	19.500
19.75 mm	metric	0.7776	19.750
25/32	fraction	0.7813	19.844
20.0 mm	metric	0.7874	20.000
51/64	fraction	0.7969	20.241
20.25 mm	metric	0.7972	20.250
20.5 mm	metric	0.8071	20.500
13/16	fraction	0.8125	20.638
20.75 mm	metric	0.8169	20.750
21.0 mm	metric	0.8268	21.000
53/64	fraction	0.8281	21.034
21.25 mm	metric	0.8366	21.250
27/32	fraction	0.8438	21.431
21.5 mm	metric	0.8465	21.500
21.75 mm	metric	0.8563	21.750
55/64	fraction	0.8594	21.828
22.0 mm	metric	0.8661	22.000
7/8	fraction	0.8750	22.225
22.25 mm	metric	0.8760	22.250
22.5 mm	metric	0.8858	22.500
57/64	fraction	0.8906	22.622
22.75 mm	metric	0.8957	22.750
23.0 mm	metric	0.9055	23.000
29/32	fraction	0.9063	23.019
23.25 mm	metric	0.9153	23.250
59/64	fraction	0.9219	23.416
23.5 mm	metric	0.9252	23.500
23.75 mm	metric	0.9350	23.750
15/16	fraction	0.9375	23.813
24.0 mm	metric	0.9449	24.000
61/64	fraction	0.9531	24.209
24.25 mm	metric	0.9547	24.250
24.5 mm	metric	0.9646	24.500
31/32	fraction	0.9688	24.606
24.75 mm	metric	0.9744	24.750
25.0 mm	metric	0.9842	25.000
63/64	fraction	0.9844	25.003
25.25 mm	metric	0.9941	25.250
1	fraction	1.0000	25.400

Common questions

What metric drill is closest to 1/4 in?: 6.35 mm is exact; the nearest standard metric drill is 6.4 mm.
What is a #7 drill in mm?: 5.105 mm (0.201 in), the 1/4-20 tap drill.

Calculators that use this data

Drill Chart & Size FinderFractional, number, letter and metric drills with decimal equivalents and a nearest-drill finder.Thread Percentage CalculatorPercent of thread from any drill for cut and form taps, with 75%, 65% and 50% tap drills.

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