Tap Drill Chart
Recommended drill sizes for cutting standard threads. Produces approximately 75% thread engagement.
SAE (National Coarse & Fine)
| Tap Size | Threads/In (NC) | Drill Size (NC) | Threads/In (NF) | Drill Size (NF) |
|---|---|---|---|---|
| #4 | 40 | #43 (0.089") | 48 | #42 (0.094") |
| #6 | 32 | #36 (0.107") | 40 | #33 (0.113") |
| #8 | 32 | #29 (0.136") | 36 | #29 (0.136") |
| #10 | 24 | #25 (0.150") | 32 | #21 (0.159") |
| #12 | 24 | #16 (0.177") | 28 | #14 (0.182") |
Register free to view the complete SAE and metric tap drill charts (all sizes).