Engineering reference

Engineering Tools

Reference data for specifying and sourcing fasteners correctly — the numbers a procurement or design engineer actually needs.

Thread pitch & tap drill size

Metric coarse and common fine pitch, with tap drill size for standard ~75% thread engagement.

SizeCoarse pitchTap drill (coarse)Fine pitchTap drill (fine)
M30.5 mm2.5 mm — —
M40.7 mm3.3 mm — —
M50.8 mm4.2 mm — —
M61.0 mm5.0 mm — —
M81.25 mm6.8 mm 1.0 mm 7.0 mm
M101.5 mm8.5 mm 1.25 mm 8.8 mm
M121.75 mm10.2 mm 1.5 mm 10.5 mm
M162.0 mm14.0 mm 1.5 mm 14.5 mm
M202.5 mm17.5 mm 1.5 mm 18.5 mm
M243.0 mm21.0 mm 2.0 mm 22.0 mm