Engineering Data 2.2 / System C

ISO 4762 SOCKET HEAD CAP SCREW — DIMENSIONS & DIN 912 EQUIVALENCE

ISO 4762:2004 specifies hexagon socket head cap screws with metric coarse pitch threads from M1.6 to M64, product grade A. It is the current international standard behind the legacy DIN 912 designation, and the two call out the same dimensions — all 20 thread sizes in our compiled table match. This page gives the complete head and socket dimensions, including the hex-key size (s) for every size.

1. Standard Identity

Standard

ISO 4762:2004 (current; EN ISO 4762:2004)

Type

Hexagon socket head cap screw

Product grade

Thread range

M1.6 – M64 (M14 non-preferred)

Dimensional equivalent

DIN 912 (20/20 sizes identical)

Property classes

ISO 898-1 (steel) / ISO 3506-1 (stainless)

2. Dimensions — M1.6 to M8

Table 1 — socket head cap screws, M1.6 to M8
Parameter (mm)	M1.6	M2	M2.5	M3	M4	M5	M6	M8
P — pitch (mm)	0.35	0.4	0.45	0.5	0.7	0.8	1	1.25
b — thread length, ref.	15	16	17	18	20	22	24	28
dk — head diameter max	3	3.8	4.5	5.5	7	8.5	10	13
dk — head diameter min	2.86	3.62	4.32	5.32	6.78	8.28	9.78	12.73
da — max	2	2.6	3.1	3.6	4.7	5.7	6.8	9.2
ds — shank diameter max	1.6	2	2.5	3	4	5	6	8
ds — shank diameter min	1.46	1.86	2.36	2.86	3.82	4.82	5.82	7.78
e — socket across corners, min	1.733	1.733	2.303	2.873	3.443	4.583	5.723	6.863
h — socket depth, max	0.34	0.51	0.51	0.51	0.6	0.6	0.68	1.02
k — head height max	1.6	2	2.5	3	4	5	6	8
k — head height min	1.46	1.86	2.36	2.86	3.82	4.82	5.7	7.64
r — min	0.1	0.1	0.1	0.1	0.2	0.2	0.25	0.4
s — hex socket nominal	1.5	1.5	2	2.5	3	4	5	6
s — socket max	1.58	1.58	2.08	2.58	3.08	4.095	5.14	6.14
s — socket min	1.52	1.52	2.02	2.52	3.02	4.02	5.02	6.02
t — min	0.7	1	1.1	1.3	2	2.5	3	4
v — max	0.16	0.2	0.25	0.3	0.4	0.5	0.6	0.8
dw — bearing face, min	2.72	3.48	4.18	5.07	6.53	8.03	9.38	12.33
w — min	0.55	0.55	0.85	1.15	1.4	1.9	2.3	3.3

Source: ISO 4762:2004, Table 1 — compiled table (see Sources).

3. Dimensions — M10 to M30

Table 2 — socket head cap screws, M10 to M30
Parameter (mm)	M10	M12	M14	M16	M20	M24	M30
P — pitch (mm)	1.5	1.75	2	2	2.5	3	3.5
b — thread length, ref.	32	36	40	44	52	60	72
dk — head diameter max	16	18	21	24	30	36	45
dk — head diameter min	15.73	17.73	20.67	23.67	29.67	35.61	44.61
da — max	11.2	13.7	15.7	17.7	22.4	26.4	33.4
ds — shank diameter max	10	12	14	16	20	24	30
ds — shank diameter min	9.78	11.73	13.73	15.73	19.67	23.67	29.67
e — socket across corners, min	9.149	11.429	13.716	15.996	19.437	21.734	25.154
h — socket depth, max	1.02	1.45	1.45	1.45	2.04	2.04	2.89
k — head height max	10	12	14	16	20	24	30
k — head height min	9.64	11.57	13.57	15.57	19.48	23.48	29.48
r — min	0.4	0.6	0.6	0.6	0.8	0.8	1
s — hex socket nominal	8	10	12	14	17	19	22
s — socket max	8.175	10.175	12.212	14.212	17.23	19.275	22.275
s — socket min	8.025	10.025	12.032	14.032	17.05	19.065	22.065
t — min	5	6	7	8	10	12	15.5
v — max	1	1.2	1.4	1.6	2	2.4	3
dw — bearing face, min	15.33	17.23	20.17	23.17	28.87	34.81	43.61
w — min	4	4.8	5.8	6.8	8.6	10.4	13.1

Source: ISO 4762:2004, Table 2 — compiled table (see Sources).

4. Dimensions — M36 to M64

Table 3 — socket head cap screws, M36 to M64
Parameter (mm)	M36	M42	M48	M56	M64
P — pitch (mm)	4	4.5	5	5.5	6
b — thread length, ref.	84	96	108	124	140
dk — head diameter max	54	63	72	84	96
dk — head diameter min	53.54	62.54	71.54	83.46	95.46
da — max	39.4	45.6	52.6	63	71
ds — shank diameter max	36	42	48	56	64
ds — shank diameter min	35.61	41.61	47.61	55.54	63.54
e — socket across corners, min	30.854	36.571	41.131	46.831	52.531
h — socket depth, max	2.89	3.06	3.91	5.95	5.95
k — head height max	36	42	48	56	64
k — head height min	35.38	41.38	47.38	55.26	63.26
r — min	1	1.2	1.6	2	2
s — hex socket nominal	27	32	36	41	46
s — socket max	27.275	32.33	36.33	41.33	46.33
s — socket min	27.065	32.08	36.08	41.08	46.08
t — min	19	24	28	34	38
v — max	3.6	4.2	4.8	5.6	6.4
dw — bearing face, min	52.54	61.34	70.34	82.26	94.26
w — min	15.3	16.3	17.5	19	22

Source: ISO 4762:2004, Table 3 — compiled table (see Sources).

5. How to read the table

dk is the head diameter, k the head height, s the hex socket width across flats (the key size), and b the reference thread length. ds is the shank diameter. Socket depth is given as h (max) and t (min). Because ISO 4762 screws are partially threaded, the actual thread length depends on the screw length — use the standard’s length tables or tell us the length and we confirm the thread length.

6. Materials and property classes

Socket head cap screws are quoted in steel class 10.9 and 12.9, and in stainless A2 / A4 on request; class 8.8 is also available. Property class selection refers to ISO 898-1 for steel and ISO 3506-1 for stainless steel. Standard finishes: zinc plating, zinc-nickel, dacromet and hot-dip galvanizing. See mechanical properties and surface treatment.

7. Equivalent standards

Standard	Relationship	Note
DIN 912	Dimensionally equivalent (cylindrical head socket screw)	20/20 sizes match in our data
DIN 7984	Low-head version — not interchangeable	Lower head height
ISO 10642	Countersunk socket screw — different head	Use where a flush head is required
ASME B18.3	Inch series socket screws — not interchangeable	Different thread and dimensions

8. How to order

State the size × length (e.g., M10 × 40), property class or stainless grade, finish, and quantity. If the drawing says DIN 912, say so — the dimensions are the same and we quote either designation.

ISO 4762 socket head cap screw — product page Request a quotation

9. FAQ

Is ISO 4762 the same as DIN 912?

Dimensionally yes. In our compiled data all 20 thread sizes match DIN 912 size by size (P, b, dk, da, ds, e, h, k, r, s, t, v, dw and w). DIN 912 is the legacy German designation; ISO 4762:2004 is the current international standard.

What does the “s” value mean?

s is the width across flats of the hex socket — the key size you need. For example an M10 socket head cap screw uses an 8 mm hex key (s = 8 mm).

Which hex key do I need?

Use the s value in the table: M3 = 2.5 mm, M4 = 3 mm, M5 = 4 mm, M6 = 5 mm, M8 = 6 mm, M10 = 8 mm, M12 = 10 mm, M16 = 14 mm, M20 = 17 mm, M24 = 19 mm.

What property classes are available?

Steel socket head cap screws are commonly supplied in 10.9 and 12.9 (our data set lists 1000 MPa / 900 MPa and 1200 MPa / 1080 MPa); class 8.8 and stainless A2 / A4 are available on request. Property class selection refers to ISO 898-1 and ISO 3506-1.

What is the difference between ISO 4762 and DIN 7984?

ISO 4762 has the standard cylindrical head; DIN 7984 is the low-head version. The heads are not interchangeable where head height matters.

Are socket head cap screws fully threaded?

No — ISO 4762 is partially threaded: b is the reference thread length, which depends on the screw length. The length tables in the standard give the exact thread length for each length.

What thread range does ISO 4762 cover?

M1.6 to M64, with (M14) as a non-preferred size. This page lists every preferred size.

Can you supply stainless or coated socket screws?

Yes — A2 / A4 stainless steel and the standard finishes (zinc plating, zinc-nickel, dacromet, hot-dip galvanizing). Confirm class and coating on the order.

10. Sources and version

Dimensions: ISO 4762:2004 hexagon socket head cap screws table, compiled in our data set (source: fasteners.eu, retrieved 2026-10-28) and cross-checked against DIN 912 — 20 of 20 thread sizes identical. Property-class values from our open data set. Per-size pages: ISO 4762 size chart. Page last reviewed: 2026-10-29.