M27 × 3 tap drill size

24.00 mm drill — or 15/16 (0.9375 in) = 82% thread

M27 coarse series, 3 mm pitch. Tap drill Ø = nominal − pitch = 27 − 3 = 24.00 mm (≈77% thread, the standard chart value).

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