Below is a table of drill and tap sizes for Unified Screw Threads – Fine, UNF.
UNF screws may not always be appropriate. Depending on the application, you may be better off using UNC fasteners.
| INCH SIZES – NATIONAL FINE |
| TAP SIZE |
DRILL SIZE |
| #1-72 |
#53 |
| #2-64 |
#50 |
| #3-56 |
#46 |
| #4-48 |
#42 |
| #5-44 |
#37 |
| #6-40 |
#33 |
| #8-36 |
#29 |
| #10-32 |
#21 |
| #12-28 |
#15 |
| 1/4-28 |
#3 |
| 5/16-24 |
I |
| 3/8-24 |
Q |
| 7/16-20 |
W |
| 1/2-20 |
29/64 |
| 9/16-18 |
33/64 |
| 5/8-18 |
37/64 |
| 3/4-16 |
11/16 |
| 7/8-14 |
13/16 |
| 1″-12 |
15/16 |
| 1-1/8-12 |
1-3/64 |
| 1-1/4-12 |
1-11/64 |
| 1-1/2-12 |
1-27/64 |
| 1-3/4-12 |
1-43/64 |
| 2″-12 |
1-59/64 |
|
Metric Tap Drill Sizes
Standard UNC Tap Drill Sizes
Standard NPT Tap Drill Sizes
