Dimensions mm · values as the standard states them Size P d1 dk k c r 1.4 1.35 – 1.4
2.2 – 2.6
0.7 – 0.9
0.42
1.4
1.6 1.55 – 1.6
2.6 – 3
0.9 – 1.1
0.48
1.6
2 1.95 – 2
3.3 – 3.7
1.1 – 1.3
0.6
1.9
2.5 2.425 – 2.5
4.2 – 4.6
1.4 – 1.6
0.75
2.4
3 2.925 – 3
4.95 – 5.45
1.65 – 1.95
0.9
2.8
4 3.9 – 4
6.75 – 7.25
2.25 – 2.55
1.2
3.8
5 4.9 – 5
8.5 – 9.1
2.85 – 3.15
1.5
4.6
6 5.9 – 6
10.2 – 10.8
3.45 – 3.75
1.8
5.7
8 7.85 – 8
13.6 – 14.4
4.6 – 5
2.4
7.5
10 9.85 – 10
14.9 – 16
6.5 – 7.4
3
8
12 11.8 – 12
17.7 – 19
7.5 – 8.4
3.6
9.5
16 15.8 – 16
23.7 – 25
10 – 10.9
4.8
13
20 19.8 – 20
30.7 – 32
13 – 13.9
6
16.5
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.
Length tolerances 3 2.8 – 3.2
4 3.7 – 4.3
5 4.7 – 5.3
6 5.7 – 6.3
8 7.7 – 8.3
10 9.7 – 10.3
12 11.6 – 12.4
16 15.6 – 16.4
20 19.5 – 20.5
25 24.5 – 25.5
30 29.5 – 30.5
35 34.5 – 35.5
40 39.5 – 40.5
Size sheet · ISO 8746
1.4
d1 pin diameter 1.35 – 1.4
dk 2.2 – 2.6
k head height 0.7 – 0.9
c 0.42
r radius of the spherical head 1.4 Standard lengths
3 · 4 · 5 · 6
Size sheet · ISO 8746
1.6
d1 pin diameter 1.55 – 1.6
dk 2.6 – 3
k head height 0.9 – 1.1
c 0.48
r radius of the spherical head 1.6 Standard lengths
3 · 4 · 5 · 6 · 8
Size sheet · ISO 8746
2
d1 pin diameter 1.95 – 2
dk 3.3 – 3.7
k head height 1.1 – 1.3
c 0.6
r radius of the spherical head 1.9 Standard lengths
3 · 4 · 5 · 6 · 8 · 10
Size sheet · ISO 8746
2.5
d1 pin diameter 2.425 – 2.5
dk 4.2 – 4.6
k head height 1.4 – 1.6
c 0.75
r radius of the spherical head 2.4 Standard lengths
3 · 4 · 5 · 6 · 8 · 10 · 12
Size sheet · ISO 8746
3
d1 pin diameter 2.925 – 3
dk 4.95 – 5.45
k head height 1.65 – 1.95
c 0.9
r radius of the spherical head 2.8 Standard lengths
4 · 5 · 6 · 8 · 10 · 12 · 16
Size sheet · ISO 8746
4
d1 pin diameter 3.9 – 4
dk 6.75 – 7.25
k head height 2.25 – 2.55
c 1.2
r radius of the spherical head 3.8 Standard lengths
5 · 6 · 8 · 10 · 12 · 16 · 20
Size sheet · ISO 8746
5
d1 pin diameter 4.9 – 5
dk 8.5 – 9.1
k head height 2.85 – 3.15
c 1.5
r radius of the spherical head 4.6 Standard lengths
6 · 8 · 10 · 12 · 16 · 20 · 25
Size sheet · ISO 8746
6
d1 pin diameter 5.9 – 6
dk 10.2 – 10.8
k head height 3.45 – 3.75
c 1.8
r radius of the spherical head 5.7 Standard lengths
8 · 10 · 12 · 16 · 20 · 25 · 30
Size sheet · ISO 8746
8
d1 pin diameter 7.85 – 8
dk 13.6 – 14.4
k head height 4.6 – 5
c 2.4
r radius of the spherical head 7.5 Standard lengths
10 · 12 · 16 · 20 · 25 · 30 · 35 · 40
Size sheet · ISO 8746
10
d1 pin diameter 9.85 – 10
dk 14.9 – 16
k head height 6.5 – 7.4
c 3
r radius of the spherical head 8 Standard lengths
12 · 16 · 20 · 25 · 30 · 35 · 40
Size sheet · ISO 8746
12
d1 pin diameter 11.8 – 12
dk 17.7 – 19
k head height 7.5 – 8.4
c 3.6
r radius of the spherical head 9.5 Standard lengths
16 · 20 · 25 · 30 · 35 · 40
Size sheet · ISO 8746
16
d1 pin diameter 15.8 – 16
dk 23.7 – 25
k head height 10 – 10.9
c 4.8
r radius of the spherical head 13 Standard lengths
20 · 25 · 30 · 35 · 40
Size sheet · ISO 8746
20
d1 pin diameter 19.8 – 20
dk 30.7 – 32
k head height 13 – 13.9
c 6
r radius of the spherical head 16.5 Standard lengths
25 · 30 · 35 · 40
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 8746:1997 preview — values match. The source publishes one identical table for DIN 1476, ISO 8746.