ANSI - ISO Drill equivalence chart.
| Drill Number |
Dia (inches) |
Equivalent Dia ISO mm |
Dia (inches) |
| 80 |
0.0135 |
0.35mm |
0.0138 |
| 79 |
0.0145 |
0.38mm |
0.0150 |
| 78 |
0.0160 |
0.40mm |
0.0157 |
| 77 |
0.0180 |
0.45mm |
0.0177 |
| 76 |
0.0200 |
0.50mm |
0.0197 |
| 75 |
0.0210 |
0.52mm |
0.0205 |
| 74 |
0.0225 |
0.58mm |
0.0228 |
| 73 |
0.0240 |
0.60mm |
0.0236 |
| 72 |
0.0250 |
0.65mm |
0.0256 |
| 71 |
0.0260 |
0.65mm |
0.0256 |
| 70 |
0.0280 |
0.70mm |
0.0276 |
| 69 |
0.0292 |
0.75mm |
0.0295 |
| 68 |
0.0310 |
1/32" |
0.3120 |
| 67 |
0.0320 |
0.82mm |
0.0323 |
| 66 |
0.0330 |
0.85mm |
0.0335 |
| 65 |
0.0350 |
0.90mm |
0.0354 |
| 64 |
0.0360 |
0.92mm |
0.0362 |
| 63 |
0.0370 |
0.95mm |
0.0374 |
| 62 |
0.0380 |
0.98mm |
0.0386 |
| 61 |
0.0390 |
1.00mm |
0.0394 |
| 60 |
0.0400 |
1.00mm |
0.0394 |
| 59 |
0.0410 |
1.05mm |
0.0413 |
| 58 |
0.0420 |
1.05mm |
0.0413 |
| 57 |
0.0430 |
1.10mm |
0.0433 |
| 56 |
0.0465 |
3/64" |
0.0469 |
| 55 |
0.0520 |
1.30mm |
0.0512 |
| 54 |
0.0550 |
1.40mm |
0.0551 |
| 53 |
0.0595 |
1.50mm |
0.0591 |
| 52 |
0.0635 |
1.60mm |
0.0630 |
| 51 |
0.0670 |
1.70mm |
0.0669 |
| 50 |
0.0700 |
1.80mm |
0.0709 |
| 49 |
0.0730 |
1.85mm |
0.0728 |
| 48 |
0.0760 |
1.95mm |
0.0768 |
| 47 |
0.0785 |
2.00mm |
0.0787 |
| 46 |
0.0810 |
2.05mm |
0.0807 |
| 45 |
0.0820 |
2.10mm |
0.0827 |
| 44 |
0.0860 |
2.20mm |
0.0866 |
| 43 |
0.0890 |
2.25mm |
0.0886 |
| 42 |
0.0935 |
3/32" |
0.0938 |
| 41 |
0.0960 |
2.45mm |
0.0965 |
| 40 |
0.0980 |
2.50mm |
0.0984 |
| 39 |
0.0995 |
2.55mm |
0.1004 |
| 38 |
0.1015 |
2.60mm |
0.1024 |
| 37 |
0.1040 |
2.65mm |
0.1043 |
| 36 |
0.1065 |
2.70mm |
0.1063 |
| 35 |
0.1100 |
2.80mm |
0.1102 |
| 34 |
0.1110 |
2.80mm |
0.1102 |
| 33 |
0.1130 |
2.85mm |
0.1122 |
| 32 |
0.1160 |
2.95mm |
0.1161 |
| 31 |
0.1200 |
3.00mm |
0.1181 |
| 30 |
0.1285 |
3.30mm |
0.1299 |
| 29 |
0.1360 |
3.50mm |
0.1378 |
| 28 |
0.1405 |
9/64" |
0.1406 |
| 27 |
0.1440 |
3.70mm |
0.1457 |
| 26 |
0.1470 |
3.70mm |
0.1457 |
| 25 |
0.1495 |
3.80mm |
0.1496 |
| 24 |
0.1520 |
3.90mm |
0.1535 |
| 23 |
0.1540 |
3.90mm |
0.1535 |
| 22 |
0.1570 |
4.00mm |
0.1575 |
| 21 |
0.1590 |
4.10mm |
0.1614 |
| 20 |
0.1610 |
4.10mm |
0.1614 |
| 19 |
0.1660 |
4.20mm |
0.1654 |
| 18 |
0.1695 |
4.30mm |
0.1693 |
| 17 |
0.1730 |
4.40mm |
0.1732 |
| 16 |
0.1770 |
4.50mm |
0.1772 |
| 15 |
0.1800 |
4.60mm |
0.1811 |
| 14 |
0.1820 |
4.60mm |
0.1811 |
| 13 |
0.1850 |
4.70mm |
0.1850 |
| 12 |
0.1890 |
4.80mm |
0.1890 |
| 11 |
0.1910 |
4.90mm |
0.1929 |
| 10 |
0.1935 |
4.90mm |
0.1929 |
| 9 |
0.1960 |
5.00mm |
0.1969 |
| 8 |
0.1990 |
5.10mm |
0.2008 |
| 7 |
0.2010 |
5.10mm |
0.2008 |
| 6 |
0.2040 |
5.20mm |
0.2047 |
| 5 |
0.2055 |
5.20mm |
0.2047 |
| 4 |
0.2090 |
5.30mm |
0.2087 |
| 3 |
0.2130 |
5.40mm |
0.2126 |
| 2 |
0.2210 |
5.60mm |
0.2205 |
| 1 |
0.2280 |
5.80mm |
0.2283 |
| A |
0.2340 |
15/64" |
0.2344 |
| B |
0.2380 |
6.00mm |
0.2362 |
| C |
0.2420 |
6.10mm |
0.2402 |
| D |
0.2460 |
6.20mm |
0.2441 |
| E |
0.2500 |
1/4" |
0.2500 |
| F |
0.2570 |
6.50mm |
0.2559 |
| G |
0.2610 |
6.60mm |
0.2598 |
| H |
0.2660 |
17/64" |
0.2656 |
| I |
0.2720 |
6.90mm |
0.2717 |
| J |
0.2770 |
7.00mm |
0.2756 |
| K |
0.2810 |
9/32" |
0.2812 |
| L |
0.2900 |
7.40mm |
0.2913 |
| M |
0.2950 |
7.50mm |
0.2953 |
| N |
0.3020 |
7.70mm |
0.3031 |
| O |
0.3160 |
8.00mm |
0.3150 |
| P |
0.3230 |
8.20mm |
0.3228 |
| Q |
0.3320 |
8.40mm |
0.3307 |
| R |
0.3390 |
8.60mm |
0.3386 |
| S |
0.3480 |
8.80mm |
0.3465 |
| T |
0.3580 |
9.10mm |
0.3583 |
| U |
0.3680 |
9.30mm |
0.3661 |
| V |
0.3770 |
3/8" |
0.3750 |
| W |
0.3860 |
9.80mm |
0.3858 |
| X |
0.3970 |
10.10mm |
0.3976 |
| Y |
0.4040 |
10.30mm |
0.4055 |
| Z |
0.4130 |
10.50mm |
0.4134 |