Below is a table of drill and tap sizes for Unified Screw Threads – Course, UNC.
UNC screws may not always be appropriate. Depending on the application, you may be better off using UNF fasteners.
| INCH SIZES – NATIONAL COARSE |
| TAP SIZE |
DRILL SIZE |
| #0-80 |
3/64″ |
| #1-64 |
#53 |
| #2-56 |
#51 |
| #3-48 |
5/64″ |
| #4-40 |
#43 |
| #5-40 |
#39 |
| #6-32 |
#36 |
| #8-32 |
#29 |
| #10-24 |
#25 |
| #12-24 |
#17 |
| 1/4-20 |
#7 |
| 5/16-18 |
F |
| 3/8-16 |
5/16 |
| 7/16-14 |
U |
| 1/2-13 |
27/64 |
| 9/16-12 |
31/64 |
| 5/8-11 |
17/32 |
| 3/4-10 |
21/32 |
| 7/8-9 |
49/64 |
| 1″-8 |
7/8 |
| 1-1/8-7 |
63/64 |
| 1-1/4-7 |
1-7/64 |
| 1-1/2-6 |
1-11/32 |
| 1-3/4-5 |
1-35/64 |
| 2″-4-1/2 |
1-25/32 |
|
Metric Tap Drill Sizes
Standard UNF Tap Drill Sizes
Standard NPT Tap Drill Sizes
