M22 × 2.5 tap drill size
19.50 mm drill — or 49/64 (0.7656 in) = 79% thread
M22 coarse series, 2.5 mm pitch. Tap drill Ø = nominal − pitch = 22 − 2.5 = 19.50 mm (≈77% thread, the standard chart value).
| Drill | Size | Thread % |
|---|---|---|
| 19.50 mm | 0.7677 in | 77% |
| 49/64 (inch) | 0.7656 in / 19.45 mm | 79% |
Rounding to your nearest stock drill moves the thread percentage only a few points. Cut taps only — roll-form taps need a larger hole. Verify before you cut.
Need a different thread percentage? Open the tap drill calculator · Metric tap chart · All calculators