Wood Screw Size Chart (Gauge, Diameter, Pilot Holes) | TaskHolt
Wood Screw Size Chart (Gauge to Inches)
A wood screw size chart showing screw gauge, the matching diameter, and recommended pilot hole sizes for hardwood and softwood.
Wood screw gauge & diameter
| Gauge | Diameter (in) | Pilot (hardwood) | Pilot (softwood) |
|---|---|---|---|
| #4 | 0.112 | 5/64 | 1/16 |
| #6 | 0.138 | 3/32 | 5/64 |
| #8 | 0.164 | 1/8 | 3/32 |
| #10 | 0.190 | 1/8 | 7/64 |
| #12 | 0.216 | 9/64 | 1/8 |
| #14 | 0.242 | 5/32 | 9/64 |
Higher gauge number = thicker screw. Always drill a pilot hole in hardwood (and near board ends) to prevent splitting. Use the pilot one size up listed above.
Frequently asked questions
What size pilot hole for a #8 wood screw?
Use about 1/8 in for hardwood and 3/32 in for softwood. The pilot should match the screw’s root (shank minus threads).
Do screw gauge numbers go up or down with size?
Up. A #12 screw is thicker than a #6. The gauge refers to the outer thread diameter.