Dimensions mm · values as the standard states them Size P s e m dw da c mw M8x1 1 13
12.73 – 13
≥ 14.38
6.44 – 6.8
≥ 11.63
8 – 8.75
0.15 – 0.6
≥ 5.15
M10x1 1 16
15.73 – 16
≥ 17.77
8.04 – 8.4
≥ 14.63
10 – 10.8
0.15 – 0.6
≥ 6.43
M10x1.25 1.25 16
15.73 – 16
≥ 17.77
8.04 – 8.4
≥ 14.63
10 – 10.8
0.15 – 0.6
≥ 6.43
M12x1.5 1.5 18
17.73 – 18
≥ 20.03
10.37 – 10.8
≥ 16.63
12 – 13
0.15 – 0.6
≥ 8.3
M12x1.25 1.25 18
17.73 – 18
≥ 20.03
10.37 – 10.8
≥ 16.63
12 – 13
0.15 – 0.6
≥ 8.3
M14x1.5 1.5 21
20.67 – 21
≥ 23.36
12.1 – 12.8
≥ 19.64
14 – 15.1
0.15 – 0.6
≥ 9.68
M16x1.5 1.5 24
23.67 – 24
≥ 26.75
14.1 – 14.8
≥ 22.49
16 – 17.3
0.2 – 0.8
≥ 11.28
M18x1.5 1.5 27
26.16 – 27
≥ 29.56
15.1 – 15.8
≥ 24.85
18 – 19.5
0.2 – 0.8
≥ 12.08
M20x1.5 1.5 30
29.16 – 30
≥ 32.95
16.9 – 18
≥ 27.7
20 – 21.6
0.2 – 0.8
≥ 13.52
M20x2 2 30
29.16 – 30
≥ 32.95
16.9 – 18
≥ 27.7
20 – 21.6
0.2 – 0.8
≥ 13.52
M22x1.5 1.5 34
33 – 34
≥ 37.29
18.1 – 19.4
≥ 31.35
22 – 23.7
0.2 – 0.8
≥ 14.48
M24x2 2 36
35 – 36
≥ 39.55
20.2 – 21.5
≥ 33.25
24 – 25.9
0.2 – 0.8
≥ 16.16
M27x2 2 41
40 – 41
≥ 45.2
22.5 – 23.8
≥ 38
27 – 29.1
0.2 – 0.8
≥ 18
M30x2 2 46
45 – 46
≥ 50.85
24.3 – 25.6
≥ 42.75
30 – 32.4
0.2 – 0.8
≥ 19.44
M33x2 2 50
49 – 50
≥ 55.37
27.4 – 28.7
≥ 46.55
33 – 35.6
0.2 – 0.8
≥ 21.92
M36x3 3 55
53.8 – 55
≥ 60.79
29.4 – 31
≥ 51.11
36 – 38.9
0.2 – 0.8
≥ 23.52
M39x3 3 60
58.8 – 60
≥ 66.44
31.8 – 33.4
≥ 55.86
39 – 42.1
0.3 – 1
≥ 25.44
M42x3 3 65
63.1 – 65
≥ 71.3
32.4 – 34
≥ 59.95
42 – 45.4
0.3 – 1
≥ 25.92
M45x3 3 70
68.1 – 70
≥ 76.95
34.4 – 36
≥ 64.7
45 – 48.6
0.3 – 1
≥ 27.52
M48x3 3 75
73.1 – 75
≥ 82.6
36.4 – 38
≥ 69.45
48 – 51.8
0.3 – 1
≥ 29.12
M52x4 4 80
78.1 – 80
≥ 88.25
40.4 – 42
≥ 74.2
52 – 56.2
0.3 – 1
≥ 32.32
M56x4 4 85
82.8 – 85
≥ 93.56
43.4 – 45
≥ 78.66
56 – 60.5
0.3 – 1
≥ 34.72
M60x4 4 90
87.8 – 90
≥ 99.21
46.4 – 48
≥ 83.41
60 – 64.8
0.3 – 1
≥ 37.12
M64x4 4 95
92.8 – 95
≥ 104.86
49.1 – 51
≥ 88.16
64 – 69.1
0.3 – 1
≥ 39.28
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.
Size sheet · ISO 8673
M8x1
s width across flats 13
e width across corners ≥ 14.38
m nut height 6.44 – 6.8
dw bearing face diameter ≥ 11.63
da transition diameter 8 – 8.75
c 0.15 – 0.6
mw ≥ 5.15 Thread · ISO 261/262
Pitch P 1
d2 7.35
d3 6.773
Tap drill 7
Stress area As 39.17 mm² Size sheet · ISO 8673
M10x1
s width across flats 16
e width across corners ≥ 17.77
m nut height 8.04 – 8.4
dw bearing face diameter ≥ 14.63
da transition diameter 10 – 10.8
c 0.15 – 0.6
mw ≥ 6.43 Thread · ISO 261/262
Pitch P 1
d2 9.35
d3 8.773
Tap drill 9
Stress area As 64.49 mm² Size sheet · ISO 8673
M10x1.25
s width across flats 16
e width across corners ≥ 17.77
m nut height 8.04 – 8.4
dw bearing face diameter ≥ 14.63
da transition diameter 10 – 10.8
c 0.15 – 0.6
mw ≥ 6.43 Thread · ISO 261/262
Pitch P 1.25
d2 9.188
d3 8.466
Tap drill 8.75
Stress area As 61.2 mm² Size sheet · ISO 8673
M12x1.5
s width across flats 18
e width across corners ≥ 20.03
m nut height 10.37 – 10.8
dw bearing face diameter ≥ 16.63
da transition diameter 12 – 13
c 0.15 – 0.6
mw ≥ 8.3 Thread · ISO 261/262
Pitch P 1.5
d2 11.026
d3 10.16
Tap drill 10.5
Stress area As 88.13 mm² Size sheet · ISO 8673
M12x1.25
s width across flats 18
e width across corners ≥ 20.03
m nut height 10.37 – 10.8
dw bearing face diameter ≥ 16.63
da transition diameter 12 – 13
c 0.15 – 0.6
mw ≥ 8.3 Thread · ISO 261/262
Pitch P 1.25
d2 11.188
d3 10.466
Tap drill 10.75
Stress area As 92.07 mm² Size sheet · ISO 8673
M14x1.5
s width across flats 21
e width across corners ≥ 23.36
m nut height 12.1 – 12.8
dw bearing face diameter ≥ 19.64
da transition diameter 14 – 15.1
c 0.15 – 0.6
mw ≥ 9.68 Thread · ISO 261/262
Pitch P 1.5
d2 13.026
d3 12.16
Tap drill 12.5
Stress area As 124.55 mm² Size sheet · ISO 8673
M16x1.5
s width across flats 24
e width across corners ≥ 26.75
m nut height 14.1 – 14.8
dw bearing face diameter ≥ 22.49
da transition diameter 16 – 17.3
c 0.2 – 0.8
mw ≥ 11.28 Thread · ISO 261/262
Pitch P 1.5
d2 15.026
d3 14.16
Tap drill 14.5
Stress area As 167.25 mm² Size sheet · ISO 8673
M18x1.5
s width across flats 27
e width across corners ≥ 29.56
m nut height 15.1 – 15.8
dw bearing face diameter ≥ 24.85
da transition diameter 18 – 19.5
c 0.2 – 0.8
mw ≥ 12.08 Thread · ISO 261/262
Pitch P 1.5
d2 17.026
d3 16.16
Tap drill 16.5
Stress area As 216.23 mm² Size sheet · ISO 8673
M20x1.5
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 ≥ 13.52 Thread · ISO 261/262
Pitch P 1.5
d2 19.026
d3 18.16
Tap drill 18.5
Stress area As 271.5 mm² Size sheet · ISO 8673
M20x2
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 ≥ 13.52 Thread · ISO 261/262
Pitch P 2
d2 18.701
d3 17.546
Tap drill 18
Stress area As 257.98 mm² Size sheet · ISO 8673
M22x1.5
s width across flats 34
e width across corners ≥ 37.29
m nut height 18.1 – 19.4
dw bearing face diameter ≥ 31.35
da transition diameter 22 – 23.7
c 0.2 – 0.8
mw ≥ 14.48 Thread · ISO 261/262
Pitch P 1.5
d2 21.026
d3 20.16
Tap drill 20.5
Stress area As 333.06 mm² Size sheet · ISO 8673
M24x2
s width across flats 36
e width across corners ≥ 39.55
m nut height 20.2 – 21.5
dw bearing face diameter ≥ 33.25
da transition diameter 24 – 25.9
c 0.2 – 0.8
mw ≥ 16.16 Thread · ISO 261/262
Pitch P 2
d2 22.701
d3 21.546
Tap drill 22
Stress area As 384.42 mm² Size sheet · ISO 8673
M27x2
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 2
d2 25.701
d3 24.546
Tap drill 25
Stress area As 495.74 mm² Size sheet · ISO 8673
M30x2
s width across flats 46
e width across corners ≥ 50.85
m nut height 24.3 – 25.6
dw bearing face diameter ≥ 42.75
da transition diameter 30 – 32.4
c 0.2 – 0.8
mw ≥ 19.44 Thread · ISO 261/262
Pitch P 2
d2 28.701
d3 27.546
Tap drill 28
Stress area As 621.2 mm² Size sheet · ISO 8673
M33x2
s width across flats 50
e width across corners ≥ 55.37
m nut height 27.4 – 28.7
dw bearing face diameter ≥ 46.55
da transition diameter 33 – 35.6
c 0.2 – 0.8
mw ≥ 21.92 Thread · ISO 261/262
Pitch P 2
d2 31.701
d3 30.546
Tap drill 31
Stress area As 760.8 mm² Size sheet · ISO 8673
M36x3
s width across flats 55
e width across corners ≥ 60.79
m nut height 29.4 – 31
dw bearing face diameter ≥ 51.11
da transition diameter 36 – 38.9
c 0.2 – 0.8
mw ≥ 23.52 Thread · ISO 261/262
Pitch P 3
d2 34.051
d3 32.319
Tap drill 33
Stress area As 864.94 mm² Size sheet · ISO 8673
M39x3
s width across flats 60
e width across corners ≥ 66.44
m nut height 31.8 – 33.4
dw bearing face diameter ≥ 55.86
da transition diameter 39 – 42.1
c 0.3 – 1
mw ≥ 25.44 Thread · ISO 261/262
Pitch P 3
d2 37.051
d3 35.319
Tap drill 36
Stress area As 1028.39 mm² Size sheet · ISO 8673
M42x3
s width across flats 65
e width across corners ≥ 71.3
m nut height 32.4 – 34
dw bearing face diameter ≥ 59.95
da transition diameter 42 – 45.4
c 0.3 – 1
mw ≥ 25.92 Thread · ISO 261/262
Pitch P 3
d2 40.051
d3 38.319
Tap drill 39
Stress area As 1205.98 mm² Size sheet · ISO 8673
M45x3
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 ≥ 27.52 Thread · ISO 261/262
Pitch P 3
d2 43.051
d3 41.319
Tap drill 42
Stress area As 1397.7 mm² Size sheet · ISO 8673
M48x3
s width across flats 75
e width across corners ≥ 82.6
m nut height 36.4 – 38
dw bearing face diameter ≥ 69.45
da transition diameter 48 – 51.8
c 0.3 – 1
mw ≥ 29.12 Thread · ISO 261/262
Pitch P 3
d2 46.051
d3 44.319
Tap drill 45
Stress area As 1603.56 mm² Size sheet · ISO 8673
M52x4
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 ≥ 32.32 Thread · ISO 261/262
Pitch P 4
d2 49.402
d3 47.093
Tap drill 48
Stress area As 1828.25 mm² Size sheet · ISO 8673
M56x4
s width across flats 85
e width across corners ≥ 93.56
m nut height 43.4 – 45
dw bearing face diameter ≥ 78.66
da transition diameter 56 – 60.5
c 0.3 – 1
mw ≥ 34.72 Thread · ISO 261/262
Pitch P 4
d2 53.402
d3 51.093
Tap drill 52
Stress area As 2143.96 mm² Size sheet · ISO 8673
M60x4
s width across flats 90
e width across corners ≥ 99.21
m nut height 46.4 – 48
dw bearing face diameter ≥ 83.41
da transition diameter 60 – 64.8
c 0.3 – 1
mw ≥ 37.12 Thread · ISO 261/262
Pitch P 4
d2 57.402
d3 55.093
Tap drill 56
Stress area As 2484.8 mm² Size sheet · ISO 8673
M64x4
s width across flats 95
e width across corners ≥ 104.86
m nut height 49.1 – 51
dw bearing face diameter ≥ 88.16
da transition diameter 64 – 69.1
c 0.3 – 1
mw ≥ 39.28 Thread · ISO 261/262
Pitch P 4
d2 61.402
d3 59.093
Tap drill 60
Stress area As 2850.78 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 (1) Dimensions cross-checked against the official ISO 8673:2012 preview — values match.