Find your tap in the left column. The drill bit next to it makes a hole the right size to cut the threads. The tap is named by its size and how far apart the threads are (the pitch). The rows highlighted in red are the taps used on this bracket.
Metric| Tap | Drill bit |
|---|
| M3 × 0.5 | 2.5 mm |
| M4 × 0.7 | 3.3 mm |
| M5 × 0.8 | 4.2 mm |
| M6 × 1.0 | 5.0 mm |
| M8 × 1.25 | 6.8 mm |
| M8 × 1.0 | 7.0 mm |
| M10 × 1.5 | 8.5 mm |
| M10 × 1.25 | 8.8 mm |
| M12 × 1.75 | 10.2 mm |
| M12 × 1.5 | 10.5 mm |
| M12 × 1.25 | 10.75 mm or 27/64″ |
| M14 × 2.0 | 12.0 mm |
| M16 × 2.0 | 14.0 mm |
Inch (UNC / UNF)| Tap | Drill bit |
|---|
| #4-40 | #43 |
| #6-32 | #36 |
| #8-32 | #29 |
| #10-24 | #25 |
| #10-32 | #21 |
| 1/4-20 | #7 |
| 1/4-28 | #3 |
| 5/16-18 | F |
| 5/16-24 | I |
| 3/8-16 | 5/16″ |
| 3/8-24 | Q |
| 7/16-14 | U |
| 7/16-20 | 25/64″ |
| 1/2-13 | 27/64″ |
| 1/2-20 | 29/64″ |