M3 Tapped Hole Drill Size — 2.5 mm

To tap an M3 thread (pitch 0.5 mm), drill a 2.5 mm hole for standard 6H tolerance. Use 2.6 mm for a looser 7H fit.

Tolerance class	Drill diameter	Pitch	Thread depth
6H (standard)	2.5 mm	0.5 mm	4–6 mm
7H (loose)	2.6 mm	0.5 mm	4–6 mm
4H (tight)	2.45 mm	0.5 mm	4–6 mm

FAQ

2.5 mm drill for standard M3 thread (6H, pitch 0.5 mm).

2.5 mm = 0.098 in. Closest imperial drill: #39 (0.0995 in) or 3/32 in (2.38 mm, slightly undersized).

Свердло 2,5 мм для різьби М3 з кроком 0,5 мм (допуск 6H).

Сверло 2,5 мм для резьбы М3 с шагом 0,5 мм (допуск 6H).

Full M3 thread data in the app
Profile viewer, tolerance calculator, 28 thread types