PROPER DRILL BIT SIZE FOR DRILLING PILOT HOLES & SHANK HOLES

SCREW GAGE
NUMBER

SHANK HOLE
HARD & SOFT WOOD

PILOT HOLE
SOFT WOOD

PILOT HOLE
HARD WOOD

0
1
2
3
4
5
6
7
8
9
10
11
12
14
16
18
20

1/16"
5/64"
3/32
7/64"
7/64"
1/8"
9/64"
5/32"
11/64"
3/16"
3/16"
13/64"
7/32"
1/4"
17/64"
19/64"
21/64"

1/64"
1/32"
1/32"
3/64"
3/64"
1/16"
1/16"
1/16"
5/64"
5/64"
3/32"
3/32"
7/64"
7/64"
9/64"
9/64"
11/64"

1/32"
1/32"
3/64"
1/16"
1/16"
5/64"
5/64"
3/32"
3/32"
7/64"
7/64"
1/8"
1/8"
9/64"
5/32"
3/16"
13/64"