Wood Screw Pilot Hole Sizes
| Screw Size |
Hard Wood |
Soft Wood |
Countersink Size |
| Tapered Bit |
Straight Bit |
Tapered Bit |
Straight Bit |
| #2 |
3/32" |
1/16" |
5/64" |
1/16" |
1/4" |
| #3 |
7/64" |
5/64" |
3/32" |
1/16" |
1/4" |
| #4 |
7/64" |
5/64" |
3/32" |
1/16" |
1/4" |
| #5 |
1/8" |
3/32" |
7/64" |
5/64" |
5/16" |
| #6 |
9/64" |
7/64" |
1/8" |
3/32" |
5/16" |
| #7 |
5/32" |
7/64" |
9/64" |
3/32" |
5/16" |
| #8 |
11/64" |
1/8" |
5/32" |
7/64" |
3/8" |
| #9 |
3/16" |
9/64" |
11/64" |
1/8" |
3/8" |
| #10 |
13/64" |
9/64" |
3/16" |
1/8" |
7/16" |
| #12 |
7/32" |
5/32" |
13/64" |
9/64" |
7/16" |
| #14 |
1/4" |
11/64" |
15/64" |
5/32" |
1/2" |
| #16 |
9/32" |
3/16" |
17/64" |
11/64" |
9/16" |
| #18 |
5/16" |
7/32" |
19/64" |
13/64" |
5/8" |
| #20 |
21/64" |
15/64" |
5/16" |
7/32" |
3/4" |
| #24 |
3/8" |
17/64" |
3/8" |
1/4" |
3/4" |