Metric Hex Nut Size Chart (Width Across Flats)
Standard width across flats and thread pitch for metric hex nuts, per ISO 4032.
| Thread | Pitch (mm) | WAF (mm) | Wrench (mm) |
|---|---|---|---|
| M3 | 0.5 | 5.5 | 5.5 |
| M4 | 0.7 | 7 | 7 |
| M5 | 0.8 | 8 | 8 |
| M6 | 1.0 | 10 | 10 |
| M8 | 1.25 | 13 | 13 |
| M10 | 1.5 | 17 | 17 |
| M12 | 1.75 | 19 | 19 |
| M16 | 2.0 | 24 | 24 |
| M20 | 2.5 | 30 | 30 |
ISO 4032 standard nuts; heavy and jam nuts differ. The wrench size equals the width across flats.
Printable PDF
Download the printer-friendly Metric Hex Nut Size Chart (Width Across Flats) as a free PDF — perfect for the shop wall or toolbox.
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