Dimensions mm · values as the standard states them Size P s e m dw da c mw M1.6 0.35 3.2
3.02 – 3.2
≥ 3.41
1.05 – 1.3
≥ 2.4
1.6 – 1.84
0.1 – 0.2
≥ 0.8
M2 0.4 4
3.82 – 4
≥ 4.32
1.35 – 1.6
≥ 3.1
2 – 2.3
0.1 – 0.2
≥ 1.1
M2.5 0.45 5
4.82 – 5
≥ 5.45
1.75 – 2
≥ 4.1
2.5 – 2.9
0.1 – 0.3
≥ 1.4
M3 0.5 5.5
5.32 – 5.5
≥ 6.01
2.15 – 2.4
≥ 4.6
3 – 3.45
0.15 – 0.4
≥ 1.7
M3.5 0.6 6
5.82 – 6
≥ 6.58
2.55 – 2.8
≥ 5
3.5 – 4
0.15 – 0.4
≥ 2
M4 0.7 7
6.78 – 7
≥ 7.66
2.9 – 3.2
≥ 5.9
4 – 4.6
0.15 – 0.4
≥ 2.3
M5 0.8 8
7.78 – 8
≥ 8.79
4.4 – 4.7
≥ 6.9
5 – 5.75
0.15 – 0.5
≥ 3.5
M6 1 10
9.78 – 10
≥ 11.05
4.9 – 5.2
≥ 8.9
6 – 6.75
0.15 – 0.5
≥ 3.9
M8 1.25 13
12.73 – 13
≥ 14.38
6.44 – 6.8
≥ 11.6
8 – 8.75
0.15 – 0.6
≥ 5.2
M10 1.5 16
15.73 – 16
DIN 17
≥ 17.77
8.04 – 8.4
≥ 14.6
10 – 10.8
0.15 – 0.6
≥ 6.4
M12 1.75 18
17.73 – 18
DIN 19
≥ 20.03
10.37 – 10.8
≥ 16.6
12 – 13
0.15 – 0.6
≥ 8.3
M14 2 21
20.67 – 21
DIN 22
≥ 23.36
12.1 – 12.8
≥ 19.6
14 – 15.1
0.15 – 0.6
≥ 9.7
M16 2 24
23.67 – 24
≥ 26.75
14.1 – 14.8
≥ 22.5
16 – 17.3
0.2 – 0.8
≥ 11.3
M18 2.5 27
26.16 – 27
≥ 29.56
15.1 – 15.8
≥ 24.9
18 – 19.5
0.2 – 0.8
≥ 12.1
M20 2.5 30
29.16 – 30
≥ 32.95
16.9 – 18
≥ 27.7
20 – 21.6
0.2 – 0.8
≥ 13.5
M22 2.5 34
33 – 34
DIN 32
≥ 37.29
18.1 – 19.4
≥ 31.4
22 – 23.7
0.2 – 0.8
≥ 14.5
M24 3 36
35 – 36
≥ 39.55
20.2 – 21.5
≥ 33.3
24 – 25.9
0.2 – 0.8
≥ 16.2
M27 3 41
40 – 41
≥ 45.2
22.5 – 23.8
≥ 38
27 – 29.1
0.2 – 0.8
≥ 18
M30 3.5 46
45 – 46
≥ 50.85
24.3 – 25.6
≥ 42.8
30 – 32.4
0.2 – 0.8
≥ 19.4
M33 3.5 50
49 – 50
≥ 55.37
27.4 – 28.7
≥ 46.6
33 – 35.6
0.2 – 0.8
≥ 21.9
M36 4 55
53.8 – 55
≥ 60.79
29.4 – 31
≥ 51.1
36 – 38.9
0.2 – 0.8
≥ 23.5
M39 4 60
58.8 – 60
≥ 66.44
31.8 – 33.4
≥ 55.9
39 – 42.1
0.3 – 1
≥ 25.4
M42 4.5 65
63.1 – 65
≥ 71.3
32.4 – 34
≥ 60
42 – 45.4
0.3 – 1
≥ 25.9
M45 4.5 70
68.1 – 70
≥ 76.95
34.4 – 36
≥ 64.7
45 – 48.6
0.3 – 1
≥ 27.5
M48 5 75
73.1 – 75
≥ 82.6
36.4 – 38
≥ 69.5
48 – 51.8
0.3 – 1
≥ 29.1
M52 5 80
78.1 – 80
≥ 88.25
40.4 – 42
≥ 74.2
52 – 56.2
0.3 – 1
≥ 32.3
M56 5.5 85
82.8 – 85
≥ 93.56
43.4 – 45
≥ 78.7
56 – 60.5
0.3 – 1
≥ 34.7
M60 5.5 90
87.8 – 90
≥ 99.21
46.4 – 48
≥ 83.4
60 – 64.8
0.3 – 1
≥ 37.1
M64 6 95
92.8 – 95
≥ 104.86
49.1 – 51
≥ 88.2
64 – 69.1
0.3 – 1
≥ 39.3
Ranges read min – max; ≤ / ≥ where the standard gives one limit, ≈ for approximate values. Sizes in (brackets) are non-preferred. Select a row for its size sheet. Cells marked DIN show where DIN 934 used a different value.
Size sheet · ISO 4032
M1.6
s width across flats 3.2
e width across corners ≥ 3.41
m nut height 1.05 – 1.3
dw bearing face diameter ≥ 2.4
da transition diameter 1.6 – 1.84
c 0.1 – 0.2
mw ≥ 0.8 Thread · ISO 261/262
Pitch P 0.35
d2 1.373
d3 1.171
Tap drill 1.25
Stress area As 1.27 mm² Size sheet · ISO 4032
M2
s width across flats 4
e width across corners ≥ 4.32
m nut height 1.35 – 1.6
dw bearing face diameter ≥ 3.1
da transition diameter 2 – 2.3
c 0.1 – 0.2
mw ≥ 1.1 Thread · ISO 261/262
Pitch P 0.4
d2 1.74
d3 1.509
Tap drill 1.6
Stress area As 2.07 mm² Size sheet · ISO 4032
M2.5
s width across flats 5
e width across corners ≥ 5.45
m nut height 1.75 – 2
dw bearing face diameter ≥ 4.1
da transition diameter 2.5 – 2.9
c 0.1 – 0.3
mw ≥ 1.4 Thread · ISO 261/262
Pitch P 0.45
d2 2.208
d3 1.948
Tap drill 2.05
Stress area As 3.39 mm² Size sheet · ISO 4032
M3
s width across flats 5.5
e width across corners ≥ 6.01
m nut height 2.15 – 2.4
dw bearing face diameter ≥ 4.6
da transition diameter 3 – 3.45
c 0.15 – 0.4
mw ≥ 1.7 Thread · ISO 261/262
Pitch P 0.5
d2 2.675
d3 2.387
Tap drill 2.5
Stress area As 5.03 mm² Size sheet · ISO 4032
M3.5
s width across flats 6
e width across corners ≥ 6.58
m nut height 2.55 – 2.8
dw bearing face diameter ≥ 5
da transition diameter 3.5 – 4
c 0.15 – 0.4
mw ≥ 2 Thread · ISO 261/262
Pitch P 0.6
d2 3.11
d3 2.764
Tap drill 2.9
Stress area As 6.78 mm² Size sheet · ISO 4032
M4
s width across flats 7
e width across corners ≥ 7.66
m nut height 2.9 – 3.2
dw bearing face diameter ≥ 5.9
da transition diameter 4 – 4.6
c 0.15 – 0.4
mw ≥ 2.3 Thread · ISO 261/262
Pitch P 0.7
d2 3.545
d3 3.141
Tap drill 3.3
Stress area As 8.78 mm² Size sheet · ISO 4032
M5
s width across flats 8
e width across corners ≥ 8.79
m nut height 4.4 – 4.7
dw bearing face diameter ≥ 6.9
da transition diameter 5 – 5.75
c 0.15 – 0.5
mw ≥ 3.5 Thread · ISO 261/262
Pitch P 0.8
d2 4.48
d3 4.019
Tap drill 4.2
Stress area As 14.18 mm² Size sheet · ISO 4032
M6
s width across flats 10
e width across corners ≥ 11.05
m nut height 4.9 – 5.2
dw bearing face diameter ≥ 8.9
da transition diameter 6 – 6.75
c 0.15 – 0.5
mw ≥ 3.9 Thread · ISO 261/262
Pitch P 1
d2 5.35
d3 4.773
Tap drill 5
Stress area As 20.12 mm² Size sheet · ISO 4032
M8
s width across flats 13
e width across corners ≥ 14.38
m nut height 6.44 – 6.8
dw bearing face diameter ≥ 11.6
da transition diameter 8 – 8.75
c 0.15 – 0.6
mw ≥ 5.2 Thread · ISO 261/262
Pitch P 1.25
d2 7.188
d3 6.466
Tap drill 6.75
Stress area As 36.61 mm² Size sheet · ISO 4032
M10
s width across flats 16
e width across corners ≥ 17.77
m nut height 8.04 – 8.4
dw bearing face diameter ≥ 14.6
da transition diameter 10 – 10.8
c 0.15 – 0.6
mw ≥ 6.4 Thread · ISO 261/262
Pitch P 1.5
d2 9.026
d3 8.16
Tap drill 8.5
Stress area As 57.99 mm² Size sheet · ISO 4032
M12
s width across flats 18
e width across corners ≥ 20.03
m nut height 10.37 – 10.8
dw bearing face diameter ≥ 16.6
da transition diameter 12 – 13
c 0.15 – 0.6
mw ≥ 8.3 Thread · ISO 261/262
Pitch P 1.75
d2 10.863
d3 9.853
Tap drill 10.25
Stress area As 84.27 mm² Size sheet · ISO 4032
M14
s width across flats 21
e width across corners ≥ 23.36
m nut height 12.1 – 12.8
dw bearing face diameter ≥ 19.6
da transition diameter 14 – 15.1
c 0.15 – 0.6
mw ≥ 9.7 Thread · ISO 261/262
Pitch P 2
d2 12.701
d3 11.546
Tap drill 12
Stress area As 115.44 mm² Size sheet · ISO 4032
M16
s width across flats 24
e width across corners ≥ 26.75
m nut height 14.1 – 14.8
dw bearing face diameter ≥ 22.5
da transition diameter 16 – 17.3
c 0.2 – 0.8
mw ≥ 11.3 Thread · ISO 261/262
Pitch P 2
d2 14.701
d3 13.546
Tap drill 14
Stress area As 156.67 mm² Size sheet · ISO 4032
M18
s width across flats 27
e width across corners ≥ 29.56
m nut height 15.1 – 15.8
dw bearing face diameter ≥ 24.9
da transition diameter 18 – 19.5
c 0.2 – 0.8
mw ≥ 12.1 Thread · ISO 261/262
Pitch P 2.5
d2 16.376
d3 14.933
Tap drill 15.5
Stress area As 192.47 mm² Size sheet · ISO 4032
M20
s width across flats 30
e width across corners ≥ 32.95
m nut height 16.9 – 18
dw bearing face diameter ≥ 27.7
da transition diameter 20 – 21.6
c 0.2 – 0.8
mw ≥ 13.5 Thread · ISO 261/262
Pitch P 2.5
d2 18.376
d3 16.933
Tap drill 17.5
Stress area As 244.79 mm² Size sheet · ISO 4032
M22
s width across flats 34
e width across corners ≥ 37.29
m nut height 18.1 – 19.4
dw bearing face diameter ≥ 31.4
da transition diameter 22 – 23.7
c 0.2 – 0.8
mw ≥ 14.5 Thread · ISO 261/262
Pitch P 2.5
d2 20.376
d3 18.933
Tap drill 19.5
Stress area As 303.4 mm² Size sheet · ISO 4032
M24
s width across flats 36
e width across corners ≥ 39.55
m nut height 20.2 – 21.5
dw bearing face diameter ≥ 33.3
da transition diameter 24 – 25.9
c 0.2 – 0.8
mw ≥ 16.2 Thread · ISO 261/262
Pitch P 3
d2 22.051
d3 20.319
Tap drill 21
Stress area As 352.5 mm² Size sheet · ISO 4032
M27
s width across flats 41
e width across corners ≥ 45.2
m nut height 22.5 – 23.8
dw bearing face diameter ≥ 38
da transition diameter 27 – 29.1
c 0.2 – 0.8
mw ≥ 18 Thread · ISO 261/262
Pitch P 3
d2 25.051
d3 23.319
Tap drill 24
Stress area As 459.41 mm² Size sheet · ISO 4032
M30
s width across flats 46
e width across corners ≥ 50.85
m nut height 24.3 – 25.6
dw bearing face diameter ≥ 42.8
da transition diameter 30 – 32.4
c 0.2 – 0.8
mw ≥ 19.4 Thread · ISO 261/262
Pitch P 3.5
d2 27.727
d3 25.706
Tap drill 26.5
Stress area As 560.59 mm² Size sheet · ISO 4032
M33
s width across flats 50
e width across corners ≥ 55.37
m nut height 27.4 – 28.7
dw bearing face diameter ≥ 46.6
da transition diameter 33 – 35.6
c 0.2 – 0.8
mw ≥ 21.9 Thread · ISO 261/262
Pitch P 3.5
d2 30.727
d3 28.706
Tap drill 29.5
Stress area As 693.55 mm² Size sheet · ISO 4032
M36
s width across flats 55
e width across corners ≥ 60.79
m nut height 29.4 – 31
dw bearing face diameter ≥ 51.1
da transition diameter 36 – 38.9
c 0.2 – 0.8
mw ≥ 23.5 Thread · ISO 261/262
Pitch P 4
d2 33.402
d3 31.093
Tap drill 32
Stress area As 816.72 mm² Size sheet · ISO 4032
M39
s width across flats 60
e width across corners ≥ 66.44
m nut height 31.8 – 33.4
dw bearing face diameter ≥ 55.9
da transition diameter 39 – 42.1
c 0.3 – 1
mw ≥ 25.4 Thread · ISO 261/262
Pitch P 4
d2 36.402
d3 34.093
Tap drill 35
Stress area As 975.75 mm² Size sheet · ISO 4032
M42
s width across flats 65
e width across corners ≥ 71.3
m nut height 32.4 – 34
dw bearing face diameter ≥ 60
da transition diameter 42 – 45.4
c 0.3 – 1
mw ≥ 25.9 Thread · ISO 261/262
Pitch P 4.5
d2 39.077
d3 36.479
Tap drill 37.5
Stress area As 1120.91 mm² Size sheet · ISO 4032
M45
s width across flats 70
e width across corners ≥ 76.95
m nut height 34.4 – 36
dw bearing face diameter ≥ 64.7
da transition diameter 45 – 48.6
c 0.3 – 1
mw ≥ 27.5 Thread · ISO 261/262
Pitch P 4.5
d2 42.077
d3 39.479
Tap drill 40.5
Stress area As 1306 mm² Size sheet · ISO 4032
M48
s width across flats 75
e width across corners ≥ 82.6
m nut height 36.4 – 38
dw bearing face diameter ≥ 69.5
da transition diameter 48 – 51.8
c 0.3 – 1
mw ≥ 29.1 Thread · ISO 261/262
Pitch P 5
d2 44.752
d3 41.866
Tap drill 43
Stress area As 1473.15 mm² Size sheet · ISO 4032
M52
s width across flats 80
e width across corners ≥ 88.25
m nut height 40.4 – 42
dw bearing face diameter ≥ 74.2
da transition diameter 52 – 56.2
c 0.3 – 1
mw ≥ 32.3 Thread · ISO 261/262
Pitch P 5
d2 48.752
d3 45.866
Tap drill 47
Stress area As 1757.83 mm² Size sheet · ISO 4032
M56
s width across flats 85
e width across corners ≥ 93.56
m nut height 43.4 – 45
dw bearing face diameter ≥ 78.7
da transition diameter 56 – 60.5
c 0.3 – 1
mw ≥ 34.7 Thread · ISO 261/262
Pitch P 5.5
d2 52.428
d3 49.252
Tap drill 50.5
Stress area As 2030.02 mm² Size sheet · ISO 4032
M60
s width across flats 90
e width across corners ≥ 99.21
m nut height 46.4 – 48
dw bearing face diameter ≥ 83.4
da transition diameter 60 – 64.8
c 0.3 – 1
mw ≥ 37.1 Thread · ISO 261/262
Pitch P 5.5
d2 56.428
d3 53.252
Tap drill 54.5
Stress area As 2362.02 mm² Size sheet · ISO 4032
M64
s width across flats 95
e width across corners ≥ 104.86
m nut height 49.1 – 51
dw bearing face diameter ≥ 88.2
da transition diameter 64 – 69.1
c 0.3 – 1
mw ≥ 39.3 Thread · ISO 261/262
Pitch P 6
d2 60.103
d3 56.639
Tap drill 58
Stress area As 2675.97 mm² Provenance
Reviewed — dimensions cross-checked against the official ISO preview; values match.
Accessed 2026-09-23 · For design and safety-critical use, consult the current edition of the standard.
Data notes (2) Dimensions cross-checked against the official ISO 4032:2012 preview — values match. The source publishes one identical table for DIN 934, ISO 4032.