ISO 7380 is the governing dimensional standard for button head socket screws. This page sets out the scope of the standard, reproduces the full size table it specifies, and lists the DIN/ISO/ASME cross-references commonly cited in datasheets and drawings.
ISO 7380 — Scope
ISO 7380 specifies the dimensions and tolerances of button head socket screws. Material, property class, surface finish and packaging are governed by separate documents in the same standards family (for example ISO 898-1 for the mechanical property classes of bolts and screws).
Tolerance & Product Grades
ISO 7380, alongside the related ISO 7380 entries on this site, specifies product grades (typically A or B for fine work and C for general engineering) and tolerance classes for the controlling dimensions. Choose the grade against the precision your application requires.
Dimensions Specified by ISO 7380
| Size | Pitch (mm) | Head diameter dk (mm) | Head height k (mm) | Hex socket s (mm) | Reference standard |
|---|---|---|---|---|---|
| M3 | 0.5 | 5.7 | 1.65 | 2.0 | ISO 7380-1 / DIN 7380 |
| M4 | 0.7 | 7.6 | 2.2 | 2.5 | ISO 7380-1 / DIN 7380 |
| M5 | 0.8 | 9.5 | 2.75 | 3.0 | ISO 7380-1 / DIN 7380 |
| M6 | 1.0 | 10.5 | 3.3 | 4.0 | ISO 7380-1 / DIN 7380 |
| M8 | 1.25 | 14.0 | 4.4 | 5.0 | ISO 7380-1 / DIN 7380 |
| M10 | 1.5 | 17.5 | 5.5 | 6.0 | ISO 7380-1 / DIN 7380 |
| M12 | 1.75 | 21.0 | 6.6 | 8.0 | ISO 7380-1 / DIN 7380 |
| M14 | 2.0 | 24.5 | 7.7 | 10.0 | ISO 7380-1 / DIN 7380 |
| M16 | 2.0 | 28.0 | 8.8 | 10.0 | ISO 7380-1 / DIN 7380 |
| M20 | 2.5 | 35.0 | 11.0 | 12.0 | ISO 7380-1 / DIN 7380 |
Equivalent Standards
ISO 7380 button head socket screws are widely cross-referenced to the same dimensional family.
When to Specify ISO 7380
Choose ISO 7380 for international engineering work and OEM supply where ISO standards are the contractual reference. It is the default modern specification for button head socket screws.