ISO 4032

Hex Nut

Hexagon nut, standard height — ISO 4032.

Hex Nut — technical drawing with reference dimensions
dmsedw
Designation d Pitch m (min–max) s e dw Weight /100 Note
M1.6 1.6 0.35 1.05–1.3 3.2 3.41 2.4 0.003 kg
M2 2.0 0.4 1.35–1.6 4.0 4.32 3.1 0.005 kg
M2.5 2.5 0.45 1.75–2 5.0 5.45 4.1 0.010 kg
M3 common 3.0 0.5 2.15–2.4 5.5 6.01 4.6 0.014 kg
M4 common 4.0 0.7 2.9–3.2 7.0 7.66 5.9 0.033 kg
M5 common 5.0 0.8 4.4–4.7 8.0 8.79 6.9 0.057 kg
M6 common 6.0 1 4.9–5.2 10.0 11.05 8.9 0.108 kg
M8 common 8.0 1.25 6.44–6.8 13.0 14.38 11.6 0.239 kg
M10 common 10.0 1.5 8.04–8.4 16.0 17.77 14.6 0.452 kg
M12 common 12.0 1.75 10.37–10.8 18.0 20.03 16.6 0.763 kg
M14 14.0 2 12.1–12.8 21.0 23.36 19.6 1.224 kg
M16 common 16.0 2 14.1–14.8 24.0 26.75 22.5 1.855 kg
M18 18.0 2.5 15.1–15.8 27.0 29.56 24.9 2.530 kg ISO 4032 property class B (wider tolerances, sizes ≥ M18).
M20 common 20.0 2.5 16.9–18 30.0 32.95 27.7 3.567 kg ISO 4032 property class B (wider tolerances, sizes ≥ M18).
M22 22.0 2.5 18.1–19.4 34.0 37.29 31.4 5.123 kg ISO 4032 property class B (wider tolerances, sizes ≥ M18).
M24 common 24.0 3 20.2–21.5 36.0 39.55 33.3 6.358 kg ISO 4032 property class B (wider tolerances, sizes ≥ M18).
M27 27.0 3 22.5–23.8 41.0 45.2 38.0 9.341 kg ISO 4032 property class B (wider tolerances, sizes ≥ M18).
M30 common 30.0 3.5 24.3–25.6 46.0 50.85 42.8 13.080 kg ISO 4032 property class B (wider tolerances, sizes ≥ M18).
M33 33.0 3.5 27.4–28.7 50.0 55.37 46.6 17.500 kg ISO 4032 property class B (wider tolerances, sizes ≥ M18).
M36 common 36.0 4 29.4–31 55.0 60.79 51.1 22.900 kg ISO 4032 property class B (wider tolerances, sizes ≥ M18).

All dimensions in mm. Weight figures are indicative (steel), per 100 pieces.

Glossary

d
Nominal (major) diameter
m
Nut height
s
Wrench size (across flats)
e
Circumscribed diameter (across corners)
dw
Bearing face diameter

Frequently asked questions

What standard governs the hex nut?

ISO 4032 — the dimensions in the table below (nominal diameter, thread pitch and all fixed geometry) are taken directly from that standard.

Are these dimensions in millimetres?

Yes — all values are in mm, matching the metric ISO/UNI standards these components are drawn from. There are no imperial variants in this table.

Why do some sizes have a note about property class B?

Above a certain size, these nuts are commonly produced to a coarser property class (B instead of A) — wider manufacturing tolerances, still fully compliant with the standard. It only affects manufacturing tolerance, not how you use the nut.

References & further reading

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