METRIC HEX NUT DIMENSIONS CHART


Metric hex nut dimensions chart according to ISO 4032. All dimensions are given in millimetres.

Metric Hex Nut Dimensions
Nut Size Thread Pitch s e m
Width Across
Flats
Width Across
Corners
Height of
the Nut
max. min. min. max. min.
M1.6 0.35 3.20 3.02 3.41 1.30 1.05
M2 0.4 4.00 3.82 4.32 1.60 1.35
M2.5 0.45 5.00 4.82 5.45 2.00 1.75
M3 0.5 5.50 5.32 6.01 2.40 2.15
M3.5* 0.6 6.00 5.82 6.58 2.80 2.55
M4 0.7 7.00 6.78 7.66 3.2 2.9
M5 0.8 8.00 7.78 8.79 4.7 4.4
M6 1 10.00 9.78 11.05 5.2 4.9
M8 1.25 13.00 12.73 14.38 6.80 6.44
M10 1.5 16.00 15.73 17.77 8.40 8.04
M12 1.75 18.00 17.73 20.03 10.80 10.37
M14* 2 21.00 20.67 23.36 12.8 12.1
M16 2 24.00 23.67 26.75 14.8 14.1
M18* 2.5 27.00 26.16 29.56 15.8 15.1
M20 2.5 30.00 29.16 32.95 18.0 16.9
M22* 2.5 34 33 37.29 19.4 18.1
M24 3 36 35 39.55 21.5 20.2
M27* 3 41 40 45.2 23.8 22.5
M30 3.5 46 45 50.85 25.6 24.3
M33* 3.5 50 49 55.37 28.7 27.4
M36 4 55.0 53.8 60.79 31.0 29.4
M39* 4 60.0 58.8 66.44 33.4 31.8
M42 4.5 65.0 63.1 71.3 34.0 32.4
M45* 4.5 70.0 68.1 76.95 36.0 34.4
M48 5 75.0 73.1 82.6 38.0 36.4
M52* 5 80.0 78.1 88.25 42.0 40.4
M56 5.5 85.0 82.8 93.56 45.0 43.4
M60* 5.5 90.0 87.8 99.21 48.0 46.4
M64 6 95.0 92.8 104.86 51.0 49.1

Note : * Non-preferred threads according to standard.

Supplements:

Link Usage
Metric hex nut dimensions calculator Calculator form of the metric hex nut dimensions chart.

Reference:

  • ISO 4032:1999, Hexagon regular nuts (style 1) — Product grades A and B