Dimensions mm · values as the standard states them Size P ds dk s e k b r t M8x1 1 ≤ 8
≤ 13
6
≥ 6.863
8
28
0.4
≥ 4
M10x1 1 ≤ 10
≤ 16
8
≥ 9.149
10
32
0.4
≥ 5
M12x1.5 1.5 ≤ 12
≤ 18
10
≥ 11.429
12
36
0.6
≥ 6
M16x1.5 1.5 ≤ 16
≤ 24
14
≥ 15.996
16
44
0.6
≥ 8
M20x1.5 1.5 ≤ 20
≤ 30
17
≥ 19.437
20
52
0.8
≥ 10
M24x2 2 ≤ 24
≤ 36
19
≥ 21.734
24
60
0.8
≥ 12
M30x2 2 ≤ 30
≤ 45
22
≥ 25.154
30
72
1
≥ 15.5
M36x3 3 ≤ 36
≤ 54
27
≥ 30.854
36
84
1
≥ 19
M42x3 3 ≤ 42
≤ 63
32
≥ 36.571
42
96
1.2
≥ 24
M46x3 3 ≤ 48
≤ 72
36
≥ 41.131
48
108
1.6
≥ 28
M56x4 4 ≤ 56
≤ 84
41
≥ 46.831
56
124
2
≥ 34
M64x4 4 ≤ 64
≤ 96
46
≥ 52.531
64
140
2
≥ 38
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 21269
M8x1
ds shank diameter ≤ 8
dk head diameter ≤ 13
s width across flats 6
e width across corners ≥ 6.863
k head height 8
b thread length 28
r fillet radius 0.4
t groove depth ≥ 4 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 21269
M10x1
ds shank diameter ≤ 10
dk head diameter ≤ 16
s width across flats 8
e width across corners ≥ 9.149
k head height 10
b thread length 32
r fillet radius 0.4
t groove depth ≥ 5 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 21269
M12x1.5
ds shank diameter ≤ 12
dk head diameter ≤ 18
s width across flats 10
e width across corners ≥ 11.429
k head height 12
b thread length 36
r fillet radius 0.6
t groove depth ≥ 6 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 21269
M16x1.5
ds shank diameter ≤ 16
dk head diameter ≤ 24
s width across flats 14
e width across corners ≥ 15.996
k head height 16
b thread length 44
r fillet radius 0.6
t groove depth ≥ 8 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 21269
M20x1.5
ds shank diameter ≤ 20
dk head diameter ≤ 30
s width across flats 17
e width across corners ≥ 19.437
k head height 20
b thread length 52
r fillet radius 0.8
t groove depth ≥ 10 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 21269
M24x2
ds shank diameter ≤ 24
dk head diameter ≤ 36
s width across flats 19
e width across corners ≥ 21.734
k head height 24
b thread length 60
r fillet radius 0.8
t groove depth ≥ 12 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 21269
M30x2
ds shank diameter ≤ 30
dk head diameter ≤ 45
s width across flats 22
e width across corners ≥ 25.154
k head height 30
b thread length 72
r fillet radius 1
t groove depth ≥ 15.5 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 21269
M36x3
ds shank diameter ≤ 36
dk head diameter ≤ 54
s width across flats 27
e width across corners ≥ 30.854
k head height 36
b thread length 84
r fillet radius 1
t groove depth ≥ 19 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 21269
M42x3
ds shank diameter ≤ 42
dk head diameter ≤ 63
s width across flats 32
e width across corners ≥ 36.571
k head height 42
b thread length 96
r fillet radius 1.2
t groove depth ≥ 24 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 21269
M46x3
ds shank diameter ≤ 48
dk head diameter ≤ 72
s width across flats 36
e width across corners ≥ 41.131
k head height 48
b thread length 108
r fillet radius 1.6
t groove depth ≥ 28 Size sheet · ISO 21269
M56x4
ds shank diameter ≤ 56
dk head diameter ≤ 84
s width across flats 41
e width across corners ≥ 46.831
k head height 56
b thread length 124
r fillet radius 2
t groove depth ≥ 34 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 21269
M64x4
ds shank diameter ≤ 64
dk head diameter ≤ 96
s width across flats 46
e width across corners ≥ 52.531
k head height 64
b thread length 140
r fillet radius 2
t groove depth ≥ 38 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 21269:2004 preview — values match.