Pilot holes guide the screw, reduce driving torque, and help the threads bite evenly into the material. This chart will help you size pilot holes correctly for your next project using wood screws.
| Screw Size |
Hardwood | Softwood | Countersink Size |
||
|---|---|---|---|---|---|
| Tapered Bit | Straight Bit | Tapered Bit | Straight Bit | ||
| #1 | 5/64″ | 1/32″ | 1/32″ | 1/64″ | 1/4″ |
| #2 | 3/32″ | 1/16″ | 1/16″ | 1/32″ | 1/4″ |
| #3 | 7/64″ | 5/64″ | 5/64″ | 3/64″ | 1/4″ |
| #4 | 7/64″ | 5/64″ | 5/64″ | 1/16″ | 1/4″ |
| #5 | 1/8″ | 3/32″ | 3/32″ | 5/64″ | 5/16″ |
| #6 | 9/64″ | 7/64″ | 7/64″ | 3/32″ | 5/16″ |
| #7 | 5/32″ | 7/64″ | 7/64″ | 7/64″ | 3/8″ |
| #8 | 11/64″ | 1/8″ | 1/8″ | 7/64″ | 3/8″ |
| #9 | 11/64″ | 9/64″ | 9/64″ | 1/8″ | 3/8″ |
| #10 | 3/16″ | 9/64″ | 9/64″ | 1/8″ | 1/2″ |
| #11 | 3/16″ | 5/32″ | 5/32″ | 9/64″ | 1/2″ |
| #12 | 7/32″ | 5/32″ | 5/32″ | 9/64″ | 1/2″ |
| #13 | 7/32″ | 11/64″ | 11/64″ | 5/32″ | 1/2″ |
| #14 | 1/4″ | 3/16″ | 3/16″ | 5/32″ | 5/8″ |
| #15 | 1/4″ | 13/64″ | 13/64″ | 11/64″ | 5/8″ |
| #16 | 17/64″ | 7/32″ | 7/32″ | 3/16″ | 5/8″ |
| #17 | 17/64″ | 15/64″ | 15/64″ | 3/16″ | 5/8″ |
| #18 | 9/32″ | 1/4″ | 1/4″ | 13/64″ | 3/4″ |
| #19 | 9/32″ | 17/64″ | 17/64″ | 7/32″ | 3/4″ |
| #20 | 5/16″ | 9/32″ | 9/32″ | 7/32″ | 3/4″ |
| #21 | 5/16″ | 19/64″ | 19/64″ | 1/4″ | 3/4″ |
| #22 | 11/32″ | 5/16″ | 5/16″ | 1/4″ | 7/8″ |
| #23 | 11/32″ | 21/64″ | 21/64″ | 17/64″ | 7/8″ |
| #24 | 3/8″ | 11/32″ | 11/32″ | 9/32″ | 7/8″ |
| #25 | 3/8″ | 23/64″ | 23/64″ | 9/32″ | 1″ |
Disclaimer:
The content on this webpage is for informational purposes only. MISUMI makes no guarantees, expressed or implied, regarding the accuracy, completeness, or validity of the information. Performance parameters, tolerances, designs, materials, or processes should not be assumed to reflect third-party suppliers’ or manufacturers’ deliverables within MISUMI’s network. Buyers are responsible for specifying their part requirements