ISO 4017 is the governing dimensional standard for hex bolts. 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 4017 — Scope
ISO 4017 specifies the dimensions and tolerances of hex bolts. 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 4017, alongside the related ISO 4014 / ISO 4017 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 4017
| Size | Pitch coarse (mm) | Width across flats s (mm) | Width across corners e min (mm) | Head height k nom (mm) | Nominal diameter d (mm) | Reference standard | Notes |
|---|---|---|---|---|---|---|---|
| M1 | 0.25 | 2.5 | 2.71 | 0.7 | 1.0 | ISO 4017 | Fully threaded |
| M1.2 | 0.25 | 3.0 | 3.28 | 0.8 | 1.2 | ISO 4017 | Fully threaded |
| M1.4 | 0.3 | 3.0 | 3.28 | 0.9 | 1.4 | ISO 4017 | Fully threaded |
| M1.6 | 0.35 | 3.2 | 3.48 | 1.1 | 1.6 | ISO 4014/4017 | Fully threaded |
| M2 | 0.4 | 4.0 | 4.32 | 1.4 | 2.0 | ISO 4014/4017 | Fully threaded |
| M2.5 | 0.45 | 5.0 | 5.45 | 1.7 | 2.5 | ISO 4014/4017 | Fully threaded |
| M3 | 0.5 | 5.5 | 6.01 | 2.0 | 3.0 | ISO 4014/4017 | Fully threaded |
| M4 | 0.7 | 7.0 | 7.66 | 2.8 | 4.0 | ISO 4014/4017 | Fully threaded |
| M5 | 0.8 | 8.0 | 8.79 | 3.5 | 5.0 | ISO 4014/4017 | Fully threaded |
| M6 | 1.0 | 10.0 | 11.05 | 4.0 | 6.0 | ISO 4014/4017 | Fully threaded |
| M8 | 1.25 | 13.0 | 14.38 | 5.3 | 8.0 | ISO 4014/4017 | Fully threaded |
| M10 | 1.5 | 16.0 | 17.77 | 6.4 | 10.0 | ISO 4014/4017 | Fully threaded |
| M12 | 1.75 | 18.0 | 20.03 | 7.5 | 12.0 | ISO 4014/4017 | Partial / fully threaded |
| M14 | 2.0 | 21.0 | 23.36 | 8.8 | 14.0 | ISO 4014/4017 | Partial / fully threaded |
| M16 | 2.0 | 24.0 | 26.75 | 10.0 | 16.0 | ISO 4014/4017 | Partial / fully threaded |
| M18 | 2.5 | 27.0 | 30.14 | 11.5 | 18.0 | ISO 4014/4017 | Partial / fully threaded |
| M20 | 2.5 | 30.0 | 33.53 | 12.5 | 20.0 | ISO 4014/4017 | Partial / fully threaded |
| M22 | 2.5 | 32.0 | 35.72 | 14.0 | 22.0 | ISO 4014/4017 | Partial / fully threaded |
| M24 | 3.0 | 36.0 | 39.98 | 15.0 | 24.0 | ISO 4014/4017 | Partial / fully threaded |
| M27 | 3.0 | 41.0 | 45.2 | 17.0 | 27.0 | ISO 4014/4017 | Partial / fully threaded |
| M30 | 3.5 | 46.0 | 50.85 | 18.7 | 30.0 | ISO 4014/4017 | Partial / fully threaded |
| M33 | 3.5 | 50.0 | 55.37 | 21.0 | 33.0 | ISO 4014/4017 | Partial / fully threaded |
| M36 | 4.0 | 55.0 | 60.79 | 22.5 | 36.0 | ISO 4014/4017 | Partial / fully threaded |
| M39 | 4.0 | 60.0 | 66.44 | 25.0 | 39.0 | ISO 4014/4017 | Partial / fully threaded |
| M42 | 4.5 | 65.0 | 71.3 | 26.0 | 42.0 | ISO 4014/4017 | Partial / fully threaded |
| M45 | 4.5 | 70.0 | 76.95 | 28.0 | 45.0 | ISO 4014/4017 | Partial / fully threaded |
| M48 | 5.0 | 75.0 | 82.6 | 30.0 | 48.0 | ISO 4014/4017 | Partial / fully threaded |
| M52 | 5.0 | 80.0 | 88.25 | 33.0 | 52.0 | ISO 4014/4017 | Partial / fully threaded |
| M56 | 5.5 | 85.0 | 93.56 | 35.0 | 56.0 | ISO 4014 | Partial / fully threaded |
| M60 | 5.5 | 90.0 | 99.21 | 38.0 | 60.0 | ISO 4014 | Partial / fully threaded |
| M64 | 6.0 | 95.0 | 104.86 | 40.0 | 64.0 | ISO 4014 | Partial / fully threaded |
Equivalent Standards
ISO 4017 (full thread) corresponds closely to DIN 933; the partially-threaded variant ISO 4014 corresponds to DIN 931.
Companion Standards
ISO 4017 controls only the geometry of hex bolts. The mechanical strength is set by ISO 898-1 (bolts and screws) or ISO 898-2 (nuts); the surface finish is governed by separate finish standards (e.g. ISO 4042 for electroplating). For corrosion testing, the relevant document is ISO 9227 (neutral salt spray).

