Workshop
Metric threads and tap drills
In short
Coarse and fine pitch M2 to M36, tap drill, nut wrench size.
Drill ≈ nominal diameter − pitch (M10: 10 − 1.5 = 8.5). The table gives the standard-series drill, rounded by ISO 2306.
Coarse pitch
| Thread | Pitch (mm) | Drill (mm) | Wrench (mm) |
|---|---|---|---|
| M2 | 0.40 | 1.60 | — |
| M2.5 | 0.45 | 2.05 | — |
| M3 | 0.50 | 2.50 | — |
| M3.5 | 0.60 | 2.90 | — |
| M4 | 0.70 | 3.30 | — |
| M5 | 0.80 | 4.20 | — |
| M6 | 1.00 | 5.00 | — |
| M8 | 1.25 | 6.80 | — |
| M10 | 1.50 | 8.50 | — |
| M12 | 1.75 | 10.20 | 18 |
| M14 | 2.00 | 12.00 | — |
| M16 | 2.00 | 14.00 | 24 |
| M18 | 2.50 | 15.50 | — |
| M20 | 2.50 | 17.50 | 30 |
| M22 | 2.50 | 19.50 | — |
| M24 | 3.00 | 21.00 | 36 |
| M27 | 3.00 | 24.00 | 41 |
| M30 | 3.50 | 26.50 | 46 |
| M33 | 3.50 | 29.50 | 50 |
| M36 | 4.00 | 32.00 | 55 |
Wrench: ISO 4032 nut, given here from M12 to M36.
Common fine pitches
| Thread | Drill (mm) |
|---|---|
| M8 × 1 | 7.00 |
| M10 × 1 | 9.00 |
| M10 × 1.25 | 8.80 |
| M12 × 1.25 | 10.80 |
| M12 × 1.5 | 10.50 |
| M14 × 1.5 | 12.50 |
| M16 × 1.5 | 14.50 |
| M18 × 1.5 | 16.50 |
| M20 × 1.5 | 18.50 |
| M22 × 1.5 | 20.50 |
| M24 × 2 | 22.00 |
| M27 × 2 | 25.00 |
| M30 × 2 | 28.00 |
| M33 × 2 | 31.00 |
| M36 × 3 | 33.00 |
Sources
Tools · Workshop
Unit converterLength, pressure, gas flow, temperature, mass and torque: one value, every unit.Bar cutting planHow many bars for a list of parts: cutting plan per bar, saw kerf, offcuts and waste rate.Level and slopePhone angle on the part → slope in %, mm/m, 1:N and rise; or a wanted slope → angle to set.Material designationDecodes S355J2+N, P265GH, 1.4404, A312 TP316L, EN AW-6060 T6…: meaning of each part, family, standard, equivalents.