Metric fasteners - Request a quote from us for anything
- Product code:
- Metrikus kötőelemek - Kérjen ajánlatot tőlünk bármire
The following summary contains the compliance and comparison of the most common DIN and ISO standards for metric fasteners (bolts, nuts, washers, threaded rods).
| DIN standard | ISO standard | Description | Notes |
|---|---|---|---|
| DIN 931 | ISO 4014 | Hex head bolt, partially threaded | Dimensions practically identical |
| DIN 933 | ISO 4017 | Hex head bolt, fully threaded | Full thread, identical wrench size |
| DIN 960 | ISO 8676 | Fine thread, partially threaded | Special application |
| DIN 961 | ISO 8677 | Fine thread, fully threaded | Special application |
📌 Note: DIN 931 and DIN 933 standards have been superseded by ISO 4014 and ISO 4017. In practice, the dimensions are compatible.
| DIN standard | ISO standard | Description | Notes |
|---|---|---|---|
| DIN 912 | ISO 4762 | Cylinder head socket cap screw | Full compliance |
| DIN 7991 | ISO 10642 | Countersunk socket cap screw | Full compliance |
| DIN 7380 | ISO 7380 | Button head socket cap screw | Partially modified head dimensions |
| DIN standard | ISO standard | Description | Notes |
|---|---|---|---|
| DIN 934 | ISO 4032 | Hex nut | ISO version with refined dimensions |
| DIN 985 | ISO 7040 | Self-locking nut (polyamide insert) | Identical dimensions |
| DIN 439 | ISO 4035 | Low hex nut | Thin design |
| DIN 1587 | ISO 1587 | Closed (cap) nut | Identical design |
| DIN standard | ISO standard | Description | Notes |
|---|---|---|---|
| DIN 125 | ISO 7089 | Plain washer | Standard design |
| DIN 9021 | ISO 7093-1 | Large outer diameter washer | “Body washer” |
| DIN 127 | ISO 8752 | Spring washer | ISO version with modified design |
| DIN 6798 | ISO 10669 | Toothed washer | External/internal serration |
| DIN standard | ISO standard | Description | Notes |
|---|---|---|---|
| DIN 975 | ISO 898-1 + ISO 261 | Threaded rod (1 m) | ISO does not have a separate product standard; references thread and strength requirements |
| DIN 976-1 | ISO 898-1 + ISO 261 | Threaded rod (short version) | Metric thread profile |
📌 Important: In the ISO system, threaded rods reference the following standards instead of a separate product standard:
- ISO 261 – metric thread dimensions
- ISO 68-1 – thread profile
- ISO 965 – thread tolerances
- ISO 898-1 – mechanical properties
| DIN designation | ISO standard | Meaning |
|---|---|---|
| 8.8 | ISO 898-1 | General structural use |
| 10.9 | ISO 898-1 | High stress application |
| 12.9 | ISO 898-1 | High strength |
7. Main differences between DIN and ISO standards
✔ ISO standards are internationally valid with unified tolerances.
✔ DIN standards are of German origin but remain widely used in commerce.
✔ Most classic DIN standards have been transitioned to ISO equivalents.
✔ Dimensional compatibility is ensured in most cases.
✔ ISO standards feature a more precise tolerance system and harmonized designation.
8. Practical commercial notes
- Products are often found on the market under DIN designations, even if manufactured according to ISO.
- In technical documentation, it is recommended to use ISO standard references.
- For EU projects, ISO or EN references are preferable.
- EN standards are in many cases harmonized versions based on ISO.