M5 × 0.8 tap drill size
4.20 mm drill — or #19 (0.1660 in) = 75% thread
M5 coarse series, 0.8 mm pitch. Tap drill Ø = nominal − pitch = 5 − 0.8 = 4.20 mm (≈77% thread, the standard chart value).
| Drill | Size | Thread % |
|---|---|---|
| 4.20 mm | 0.1654 in | 77% |
| #19 (inch) | 0.1660 in / 4.22 mm | 75% |
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