Decimal Chart

Fraction Wire Letter Decimal (Inches) Metric (MM) Tap Size Fraction Wire Letter Decimal (Inches) Metric (MM) Tap Size Fraction Wire Letter Decimal (Inches) Metric (MM) Tap Size
80 0.0135 0.343 28 0.1405 3.569 T 0.3580 9.093
79 0.0145 0.368 9/64 0.1406 3.572 23/64 0.3594 9.128
1/64 0.0156 0.396 27 0.1440 3.658 U 0.3680 9.347 7/16-14
78 0.0160 0.406 26 0.1470 3.734 3/8 0.3750 9.525
77 0.0180 0.457 25 0.1495 3.797 10-24 V 0.3770 9.576
76 0.0200 0.508 24 0.1520 3.861 W 0.3860 9.804
75 0.0210 0.533 23 0.1540 3.912 25/64 0.3906 9.922 7/16-20
74 0.0225 0.572 5/32 0.1562 3.969 X 0.3970 10.084
73 0.0240 0.610 22 0.1570 3.988 Y 0.4040 10.262
72 0.0250 0.635 21 0.1590 4.039 10-32 13/32 0.4062 10.319
71 0.0260 0.660 20 0.1610 4.089 Z 0.413 10.490
70 0.0280 0.711 19 0.1660 4.216 27/64 0.4219 10.716 1/2-13
69 0.0292 0.742 18 0.1695 4.305 7/16 0.4375 11.113 1/4-18 NPT
68 0.0310 0.787 11/64 0.1719 4.366 29/64 0.4531 11.509 1/2-20
1/32 0.0312 0.794 17 0.1730 4.394 15/32 0.4688 11.906
67 0.0320 0.813 16 0.1770 4.496 12-24 31/64 0.4844 12.303 9/16-12
66 0.0330 0.838 15 0.1800 4.572 1/2 0.5000 12.700
65 0.0350 0.889 14 0.1820 4.623 12-28 33/64 0.5156 13.097 9/16-18
64 0.0360 0.914 13 0.185 4.699 17/32 0.5312 13.494 5/8-11
63 0.0370 0.940 3/16 0.1875 4.763 35/64 0.5469 13.891
62 0.0380 0.965 12 0.1890 4.801 9/16 0.5625 14.288
61 0.0390 0.991 11 0.1910 4.851 37/64 0.5781 14.684 5/8-18
3/8-18 NPT
60 0.0400 1.016 10 0.1935 4.915 19/32 0.5937 15.081
59 0.0410 1.041 9 0.1960 4.978 39/64 0.6094 15.478
58 0.0420 1.067 8 0.1990 5.055 5/8 0.6250 15.875
57 0.0430 1.092 7 0.2010 5.105 1/4-20 41/64 0.6406 16.272
56 0.0465 1.181 13/64 0.2031 5.159 21/32 0.6562 16.669 3/4-10
3/64 0.0469 1.191 0-80 6 0.2040 5.182 43/64 0.6719 17.066
55 0.0520 1.321 5 0.2055 5.220 11/16 0.6875 17.463 3/4-16
54 0.0550 1.397 4 0.2090 5.309 45/64 0.7031 17.859
53 0.0595 1.511 1-64
1-72		 3 0.2130 5.410 1/4-28 23/32 0.7187 18.256 1/2-14 NPT
1/16 0.0625 1.588 7/32 0.2188 5.556 47/64 0.7344 18.653
52 0.0635 1.613 2 0.2210 5.613 3/4 0.7500 19.050
51 0.0670 1.702 1 0.2280 5.791 49/64 0.7656 19.447 7/8-9
50 0.0700 1.778 2-56
2-64		 A 0.2340 5.944 25/32 0.7812 19.844
49 0.0730 1.854 15/64 0.2344 5.953 51/64 0.7969 20.241
48 0.0760 1.930 B 0.2380 6.045 13/16 0.8125 20.638 7/8-14
5/64 0.0781 1.984 C 0.2420 6.147 53/64 0.2821 21.034
47 0.0785 1.994 3-48 D 0.2460 6.248 27/32 0.8437 21.431
46 0.0810 2.057 1/4 E 0.2500 6.350 55/64 0.8594 21.828
45 0.0820 2.083 3-56 F 0.2570 6.528 5/16-18 7/8 0.8750 22.225 1-8
44 0.0860 2.184 G 0.2610 6.629 57/64 0.8906 22.622
43 0.0890 2.261 4-40 17/64 0.2656 6.747 29/32 0.9062 23.019
42 0.0935 2.375 4-48 H 0.2660 6.756 59/64 0.9219 23.416 1-12
3/4-14 NPT
3/32 0.0938 2.383 I 0.2720 6.909 5/16-24 15/16 0.9375 23.813
41 0.0960 2.438 J 0.2770 7.036 61/64 0.9531 24.209
40 0.0980 2.489 K 0.2810 7.137 31/32 0.9687 24.606
39 0.0995 2.527 9/32 0.2812 7.144 63/64 0.9844 25.003 1-1/8-7
38 0.1015 2.578 5-40 L 0.2900 7.366 1 1.0000 25.400
37 0.1040 2.642 5-44 M 0.2950 7.493 1-3/64 1.0469 26.591 1-1/8-12
36 0.1065 2.705 6-32 19/64 0.2969 7.541 1-7/64 1.1094 28.178 1-1/4-7
7/64 0.1094 2.779 N 0.3020 7.671 1-1/8 1.1250 28.575
35 0.1100 2.794 5/16 0.3125 7.938 3/8-16 1-11/64 1.1719 29.766 1-1/4-12
34 0.1110 2.819 O 0.3160 8.026 1-7/32 1.2188 30.956 1-3/8-6
33 0.1130 2.870 6-40 P 0.3230 8.204 1-1/4 1.2500 31.750
32 0.1160 2.946 21/64 0.3281 8.334 1-19/64 1.2969 32.941 1-3/8-12
31 0.1200 3.048 Q 0.3320 8.433 3/8-24 1-11/32 1.3438 34.131 1-1/2-6
1/8 0.1250 3.175 R 0.3390 8.611 1-3/8 1.3750 34.925
30 0.1285 3.264 11/32 0.3438 8.731 1/8-27 NPT 1-27/64 1.4219 36.116 1-1/2-12
29 0.1360 3.454 8-32
8-36		 S 0.3480 8.839 1-1/2 1.5000 38.100

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