DIN 6923 is the governing dimensional standard for hex flange nuts. 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.
DIN 6923 — Scope
DIN 6923 specifies the dimensions and tolerances of hex flange nuts. 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
DIN 6923, alongside the related ISO 4161 / DIN 6923 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 DIN 6923
| Size | Pitch (mm) | Flange diameter dc (mm) | Nut height m (mm) | Width across flats s (mm) | Reference standard |
|---|---|---|---|---|---|
| M5 | 0.8 | 11.8 | 5.0 | 8.0 | ISO 4161 / DIN 6923 |
| M6 | 1.0 | 14.2 | 6.0 | 10.0 | ISO 4161 / DIN 6923 |
| M8 | 1.25 | 17.9 | 8.0 | 13.0 | ISO 4161 / DIN 6923 |
| M10 | 1.5 | 21.8 | 10.0 | 15.0 | ISO 4161 / DIN 6923 |
| M12 | 1.75 | 26.0 | 12.0 | 18.0 | ISO 4161 / DIN 6923 |
| M14 | 2.0 | 29.9 | 14.0 | 21.0 | ISO 4161 / DIN 6923 |
| M16 | 2.0 | 34.5 | 16.0 | 24.0 | ISO 4161 / DIN 6923 |
| M20 | 2.5 | 42.8 | 20.0 | 30.0 | ISO 4161 / DIN 6923 |
| M24 | 3.0 | 51.1 | 24.0 | 36.0 | ISO 4161 / DIN 6923 |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Hex Flange Nuts page. Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
When to Specify DIN 6923
DIN 6923 is still widely used in European mechanical engineering and as a cross-reference on legacy drawings; its ISO equivalent is preferred for new designs.