TAP AND DRILL SIZE CHART
for more information.
| THREADSIZE | DRILL DIAMETER
Coarse Thread | TAP DRILLSIZE |
| 1-64 | .0595 | No. 53 |
| 2-56 | .0700 | No. 50 |
| 3-48 | .0785 | No. 47 |
| 4-40 | .0890 | No. 43 |
| 5-40 | .1015 | No. 38 |
| 6-32 | .1065 | No. 36 |
| 8-32 | .1360 | No. 29 |
| 10-24 | .1495 | No. 25 |
| 12-24 | .1770 | No. 16 |
| 1/4-20 | .2010 | No. 7 |
| 5/16-18 | .2570 | ‘F’ |
| 3/8-16 | .3125 | 5/16 |
| 7/16-14 | .3680 | ‘U’ |
| 1/2-13 | .4219 | 27/64 |
| 9/16-12 | .4844 | 31/64 |
| 5/8-11 | .5312 | 17/32 |
| 3/4-10 | .6562 | 21/32 |
| 7/8-9 | .7656 | 49/64 |
| 1″-8 | .8750 | 7/8 |
| Fine Thread | ||
| 0-80 | .0469 | 3/64 |
| 1-72 | .0595 | No. 53 |
| 2-64 | .0700 | No. 50 |
| 3-56 | .0820 | No. 45 |
| 4-48 | .0935 | No. 42 |
| 5-44 | .1040 | No. 37 |
| 6-40 | .1130 | No. 33 |
| 8-36 | .1360 | No. 29 |
| 10-32 | .1590 | No. 21 |
| 12-28 | .1820 | No. 14 |
| 1/4-28 | .2130 | No. 3 |
| 5/16-24 | .2720 | ‘I’ |
| 3/8-24 | .3320 | ‘Q’ |
| 7/16-20 | .3906 | 25/64 |
| 1/2-20 | .4531 | 29/64 |
| 9/16-18 | .5156 | 33/64 |
| 5/8-18 | .5781 | 37/64 |
| 3/4-16 | .6875 | 11/16 |
| 7/8-14 | .8125 | 13/16 |
| 1″-14 | .9375 | 59/64 |
