| Machine Screw Size | Number of Threads Per Inch | Minor Dia. | Tap Drills | Clearance Hole Drills | |||||||
Aluminum, Brass & Plastics 75% Thread |
Stainless Steel, Steels & Iron 50% Thread |
All Materials | |||||||||
| Close Fit | Free Fit | ||||||||||
| No. or Dia. | Major Dia. | Drill Size | Decimal Equiv. | Drill Size | Decimal Equiv. | Drill Size | Decimal Equiv. | Drill Size | Decimal Equiv. | ||
3/4 |
.7500 |
10 | .6273 | 21/32 | .6562 | 11/16 | .6875 | 49/64 |
.7656 |
25/32 |
.7812 |
| 16 | .6733 | 11/16 | .6875 | 45/64 | .7031 | ||||||
| 20 | .6887 | 45/64 | .7031 | 23/32 | .7188 | ||||||
| 13/16 | .8125 | 20 | .7512 | 49/64 | .7656 | 25/32 | .7812 | 53/64 | .8281 | 27/32 | .8438 |
| 7/8 | .8750 | 9 | .7387 | 49/64 | .7656 | 51/64 | .7969 | 57/64 | .8906 | 29/32 | .9062 |
| 14 | .7874 | 13/16 | .8125 | 53/64 | .8281 | ||||||
| 20 | .8137 | 53/64 | .8281 | 27/32 | .8438 | ||||||
| 15/16 | .9375 | 20 | .8762 | 57/64 | .8906 | 29/32 | .9062 | 61/64 | .9531 | 31/32 | .9688 |
| 1 | 1.000 | 8 | .8466 | 7/8 | .8750 | 59/64 | .9219 | 1-1/64 | 1.0156 | 1-1/32 | 1.0313 |
| 12 | .8978 | 15/16 | .9375 | 61/64 | .9531 | ||||||
| 20 | .9387 | 61/64 | .9531 | 31/32 | .9688 | ||||||
| 1-1/16 | 1.0625 | 18 | .9943 | 1.000 | 1.000 | 1-1/64 | 1.0156 | 1-5/64 | 1.0781 | 1-3/32 | 1.0938 |
| 1-1/8 | 1.1250 | 7 | .9497 | 63/64 | .9844 | 1-1/32 | 1.0313 | 1-9/64 | 1.1406 | 1-5/32 | 1.1562 |
| 12 | 1.0228 | 1-3/64 | 1.0469 | 1-5/64 | 1.0781 | ||||||
| 18 | 1.0568 | 1-1/16 | 1.0625 | 1-5/64 | 1.0781 | ||||||
| 1-3/16 | 1.1875 | 18 | 1.1193 | 1-1/8 | 1.1250 | 1-9/64 | 1.1406 | 1-13/64 | 1.2031 | 1-7/32 | 1.2188 |
| Tables for other screw sizes | #0 - #6 |
| #8 - 3/8 | |
| 7/16 - 11/16 | |
| 1-1/4 - 1-3/4 |