American Wood Screw Guide
The chart below will give the user the various dimensions for American Wood screws. All dimensions are in inches. The shank pilot hole is the one which will clear the thickest part of the screw body.
| Screw Gauge | Body Diameter | Shank Pilot Hole | Pilot Hole in Softwood | Pilot Hole in Hardwood |
| 0 | 0.060 | 1/16 | 1/64 | 1/32 |
| 1 | 0.073 | 5/64 | 1/32 | 1/32 |
| 2 | 0.086 | 3/32 | 1/32 | 3/64 |
| 3 | 0.099 | 7/64 | 3/64 | 1/16 |
| 4 | 0.112 | 7/64 | 3/64 | 1/16 |
| 5 | 0.125 | 1/8 | 1/16 | 5/64 |
| 6 | 0.138 | 9/64 | 1/16 | 5/64 |
| 7 | 0.151 | 5/32 | 1/16 | 3/32 |
| 8 | 0.164 | 11/64 | 5/64 | 3/32 |
| 9 | 0.177 | 3/16 | 5/64 | 7/64 |
| 10 | 0.190 | 3/16 | 3/32 | 7/64 |
| 11 | 0.203 | 13/64 | 3/32 | 1/8 |
| 12 | 0.216 | 7/32 | 7/64 | 1/8 |
| 14 | 0.242 | 1/4 | 7/64 | 9/64 |
| 16 | 0.268 | 17/64 | 9/64 | 5/32 |
| 18 | 0.294 | 19/64 | 9/64 | 3/16 |
| 20 | 0.320 | 21/64 | 11/64 | 13/64 |
| 24 | 0.372 | 3/8 | 3/16 | 7/32 |