DIN 933 dimensions chart is a reliable and precise metric dimensions chart of fully threaded hex bolts from M2 to M64. When selecting fasteners for engineering drawings, bills of material and procurement, it is essential to have accurate dimensional information for width across flats, head height, thread pitch and nominal weight.
The two specifications DIN 933 and ISO 4017 are often used interchangeably but they are not exactly the same in all sizes. The dimensions are different at the key width across flats M10 M12 M14 M22. This guide covers the full DIN 933 specifications including the equivalent ISO 4017, short bolt thread length exceptions, material grades and weight calculations. More information about the standards is offered on the DIN standards hub.
What Is a DIN 933 Hex Bolt
DIN 933 is a German industrial standard covering hexagon head bolts with a full thread run along the entire shank, in coarse metric pitch, from M1.6 up to M52. With the entire length of the thread being perforated, the DIN 933 bolts can be used for sections of different thicknesses in the clamped material as well as for the entire length of the grip as in the case of thin material assemblies, adjustable clamps and general purpose fastenings. That is where DIN 933 differs from the alternative which is only partially threaded (also known as DIN 931 or ISO 4014) that has an unthreaded portion of shank under the head. The partially threaded dimensions are shown here.
DIN 933 Dimensions Chart (Metric, M2 to M64)
| Size | DIN 933 WAF max (mm) | ISO 4017 WAF max (mm) | Head Height k max (mm) | Thread Pitch (mm) |
| M1.6 | 3.20 | 3.20 | 1.1 | 0.35 |
| M1.8 | 3.50 | 3.50 | 1.2 | 0.35 |
| M2 | 4.00 | 4.00 | 1.4 | 0.40 |
| M2.5 | 5.00 | 5.00 | 1.7 | 0.45 |
| M3 | 5.50 | 5.50 | 2.0 | 0.50 |
| M4 | 7.00 | 7.00 | 2.8 | 0.70 |
| M5 | 8.00 | 8.00 | 3.5 | 0.80 |
| M6 | 10.00 | 10.00 | 4.0 | 1.00 |
| M8 | 13.00 | 13.00 | 5.3 | 1.25 |
| M10 | 17.00 | 16.00 | 6.4 | 1.50 |
| M12 | 19.00 | 18.00 | 7.5 | 1.75 |
| M14 | 22.00 | 21.00 | 8.8 | 2.00 |
| M16 | 24.00 | 24.00 | 10.0 | 2.00 |
| M18 | 27.00 | 27.00 | 11.5 | 2.50 |
| M20 | 30.00 | 30.00 | 12.5 | 2.50 |
| M22 | 32.00 | 34.00 | 14.0 | 2.50 |
| M24 | 36.00 | 36.00 | 15.0 | 3.00 |
| M27 | 41.00 | 41.00 | 17.0 | 3.00 |
| M30 | 46.00 | 46.00 | 18.7 | 3.50 |
| M33 | 50.00 | 50.00 | 21.0 | 3.50 |
| M36 | 55.00 | 55.00 | 22.5 | 4.00 |
| M39 | 60.00 | 60.00 | 25.0 | 4.00 |
| M42 | 65.00 | 65.00 | 26.0 | 4.50 |
| M45 | 70.00 | 70.00 | 28.0 | 4.50 |
| M48 | 75.00 | 75.00 | 30.0 | 5.00 |
| M52 | 80.00 | 80.00 | 33.0 | 5.00 |
| M56 | N/A | 85.00 | 35.0 | 5.50 |
| M60 | N/A | 90.00 | 38.0 | 5.50 |
| M64 | N/A | 95.00 | 40.0 | 6.00 |
Where DIN 933 and ISO 4017 Differ
DIN 933 and ISO 4017 are frequently treated as interchangeable, and at most sizes they are. But four sizes carry a real dimensional difference in width across flats, and the size range itself differs at the top end.
| Size | DIN 933 WAF max (mm) | ISO 4017 WAF max (mm) | Difference |
| M10 | 17.00 | 16.00 | ISO smaller |
| M12 | 19.00 | 18.00 | ISO smaller |
| M14 | 22.00 | 21.00 | ISO smaller |
| M22 | 32.00 | 34.00 | ISO larger |
DIN 933 Weight Chart (kg per 1,000 pieces)
| Length (mm) | M6 | M8 | M10 | M12 | M16 | M20 |
| 20 | 0.55 | 1.30 | 2.55 | 4.35 | 10.10 | 19.60 |
| 25 | 0.65 | 1.48 | 2.85 | 4.82 | 11.00 | 21.10 |
| 30 | 0.75 | 1.65 | 3.15 | 5.30 | 11.90 | 22.60 |
| 40 | 0.95 | 2.05 | 3.75 | 6.25 | 13.70 | 25.60 |
| 60 | 1.35 | 2.85 | 4.95 | 8.15 | 17.30 | 31.60 |
| 80 | 1.75 | 3.65 | 6.15 | 10.05 | 20.90 | 37.60 |
DIN 933 vs DIN 931 (Full Thread vs Partial Thread)
The two standards are frequently confused because they describe the same head style and pitch series, differing only in how much of the shank is threaded. DIN 933 threads the full shank; DIN 931 (aligned with ISO 4014) leaves a smooth, unthreaded shank section sized to the bolt’s grip length. Choose DIN 933 where the clamped thickness may vary or where maximum thread engagement is needed; choose DIN 931 where a smooth shank section improves shear resistance or alignment in a fixed clamped thickness. Full dimensional data for the partial-thread version is available on our DIN 931 / ISO 4014 dimensions chart.
Frequently Asked Questions
1. Is DIN 933 still an active standard?
2. Is DIN 933 the same as ISO 4017?
3. What sizes does DIN 933 cover?
4. How is DIN 933 bolt weight calculated?
5. What is the difference between DIN 933 and DIN 931?
6. Which grades are DIN 933 hex bolts available in?
7. Do DIN 933 bolts always thread all the way to the head?
7. What thread standards do A2-70 and Grade 8.8 bolts share?
