If you've ever received a drawing calling out DIN 912 and a supplier quote offering ISO 4762, you've faced one of the most common cross-referencing questions in the fastener industry. The short answer: they describe the same product — the metric hexagon socket head cap screw — and are fully interchangeable. But the transition did change a few things around the edges, and those edges are exactly where sourcing surprises happen.
Dimensionally Identical, Fully Interchangeable
Both standards specify the same dimensional requirements for socket head cap screws: cylindrical head roughly 1.5× the nominal diameter, head height approximately equal to the diameter, internal hexagon drive. An M10 × 50 to either standard is physically and functionally the same screw. DIN 912 has been formally withdrawn; the current designation is ISO 4762 (DIN EN ISO 4762 in Germany), and it should be the reference on new drawings.
So where do the two differ? Not in the screw — in the catalogue around it.
Change 1: The Size Range Shrank at Both Ends
| Aspect | DIN 912 | ISO 4762 |
|---|---|---|
| Nominal size range | M1.4 – M100 | M1.6 – M64 |
| Fine thread coverage | No dedicated standard | ISO 12474 |
| Status | Withdrawn | Active |
DIN 912 covered an enormous span, from M1.4 miniatures up to M100. ISO 4762 trimmed the range to M1.6 through M64.
What this means in practice: M1.4 socket screws didn't vanish from the world, but they lost their mainstream standard home — expect longer lead times, fewer stocking distributors, and manufacturer-specific supply. At the top end, very large socket cap screws above M64 similarly become special-order territory referencing legacy or works standards. If your BOM lives at either extreme, flag it early in the RFQ rather than discovering it at quoting.
Change 2: Fine Threads Got Their Own Standard
DIN 912 never had a dedicated fine-thread companion — fine-pitch socket screws were handled ad hoc. The ISO system fixed this by publishing ISO 12474: hexagon socket head cap screws with metric fine pitch thread. If your application needs fine pitch (thin-wall tapped sections, fine adjustment, vibration-sensitive joints), the correct modern callout is ISO 12474, not "ISO 4762 fine thread."
Change 3: Preference Diameters Were Rationalised
ISO 4762 also pruned the catalogue, removing most second- and third-preference diameters that DIN 912 carried — with M14 surviving as the notable exception thanks to persistent market demand. The practical effect is a cleaner, more stockable size list: if a legacy drawing calls up an odd intermediate diameter, check current availability before assuming it's a shelf item.
What to Do With a DIN 912 Callout
- Buyers: product certified to ISO 4762 satisfies a DIN 912 callout in virtually every commercial scenario; confirm documentation wording at order stage if the customer's QA is strict.
- Engineers: reference ISO 4762 (and ISO 12474 for fine pitch) on new drawings; keep an eye on sizes outside M1.6–M64 inherited from old designs.
- Both: treat odd diameters and range extremes as long-lead items, not catalogue stock.
The Bottom Line
DIN 912 and ISO 4762 are the same screw with different paperwork — the real changes are in the range (M1.6–M64), the arrival of ISO 12474 for fine threads, and a rationalised diameter list. Specify ISO 4762, know where the catalogue edges moved, and this classic cross-reference will never slow a project down.