Metric hexagon socket head cap screw dimensions including M3, M4, M5, M6, M8, M10, M12, etc., screw sizes are shown in the following chart according to ISO 4762:2004 standard.

ISO 4762 specifies the properties of hexagon socket cap screws with coarse pitch thread from M1.6 up to and including M64.

Some important notes from ISO 4762 standard:

- Thread: 5g6g for Grade 12.9, 6g for other classes

- Mechanical Properties: For steel socket head cap screws with sizes ≥M3 and ≤M39, property classes are 8.8, 10.9 and 12.9. For stainless steel socket head cap screws with sizes ≤M24, property classes are A2-70, A3-70, A4-70 and A5-70. For stainless steel socket head cap screws with sizes >M24 and ≤M39, property classes are A2-50, A3-50, A4-50 and A5-50.

- Finish: For steel screws, electroplating per ISO 4042 and zinc flake coatings per ISO 10683. For stainless steel screws, plain finish.

- Designation: Hexagon socket head cap screw ISO 4762 - M6 x 35 - 10.9 (M6 thread with 35 mm length and property class 10.9)

- Approximate masses of steel screws are given in the Annex of the standard.

Metric hexagon socket head cap screw dimensions:

Thread Size [d]
Nominal Length [l] Note 1

Note 1: The range of commercial lengths is given in the list. Consult manufacturer for availability of other lengths.


Dimensions of Metric Socket Hex Cap Screws
Parameter Value
Thread Size d --- ---
Thread Pitch P --- mm
Head Diameter [dk] dk,max ---
dk,max ---
dk,min ---
Max. Fillet Transition Diameter da,max ---
Body Diameter [ds] Note 1 ds,max ---
ds,min ---
Min. Hexagon Socket Size
Across the Corners
emin ---
Head Height [k] kmax ---
kmin ---
Hexagon Socket Size snom ---
smax ---
smin ---
Min. Depth of Driving Feature tmin ---
Max. Chamfer or Radius vmax ---
Diameter of the Bearing Face dw,min ---
Min. Thickness between Driving
Feature and Bearing Face
wmin ---
Approximate Mass Note 2 m --- kg/
1000 pc.
Screw Length lnom --- mm 
lmax ---
lmin ---
Max. Grip Length lg,max ---
Min. Shank Length ls,min ---
Thread Length bref ---
Note  ---
Max. Fillet Length lf,max --- mm
Fillet Radius rmax ---
rmin ---

Note:1 ds applies if values of ls,min are specified.

Note:2 (ρ=7.85 kg/dm3)


Link Usage
Counterbore Hole Dimensions for Metric Socket Head Cap Screws Covers recommended clearance and counterbore hole sizes for metric socket head cap screws from M1.6 through M48
Metric Thread Calculator Calculates basic major, minor and pitch diameters of the metric external (bolt) thread and internal (nut) thread according to ISO 724:1993 standard. In addition to basic size calculations, tolerance calculations of different tolerance classes can be done according to ISO 965-1:1998 and ISO 965-2:1998 standards.


  • ISO 4762:2004, Hexagon Socket Head Cap Screws