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. But the details behind that answer matter for anyone writing specifications, reviewing RFQs, or managing certification requirements.
What the Two Standards Cover
Both standards define cylindrical (cheese) head cap screws with an internal hexagon drive, the workhorse fastener of machine building, tooling, and equipment assembly. Typical geometry is a head diameter of roughly 1.5× the nominal thread diameter and a head height approximately equal to the nominal diameter, allowing the screw to sit flush in a counterbored hole.
DIN 912 is the original German national standard, in use for decades and still deeply embedded in engineering drawings worldwide. ISO 4762 is the international standard that superseded it — in Germany, the current designation is DIN EN ISO 4762, and DIN 912 has been formally withdrawn as an active standard.
Are They Interchangeable?
For virtually all practical purposes, yes. The two standards are dimensionally aligned, and product manufactured to ISO 4762 will fit applications designed around DIN 912. The differences that do exist are confined to minor tolerance details — small refinements in head and socket tolerancing and the under-head transition — rather than functional dimensions. Thread, key engagement, and head envelope remain compatible.
Side-by-Side Summary
| Attribute | DIN 912 | ISO 4762 |
|---|---|---|
| Product | Socket head cap screw | Socket head cap screw |
| Status | Withdrawn (historical) | Current international standard |
| Regional designation | Legacy German (DIN) | DIN EN ISO 4762 in Germany |
| Thread | Metric coarse (fine per related specs) | Metric coarse |
| Common property classes | 8.8, 10.9, 12.9 | 8.8, 10.9, 12.9 |
| Stainless grades | A2-70, A4-80 | A2-70, A4-80 |
| Interchangeability | Fully interchangeable in practice | Fully interchangeable in practice |
What This Means in Practice
For buyers: A quote against ISO 4762 satisfies a DIN 912 callout in almost every commercial scenario. If your customer's drawing insists on "DIN 912" verbatim, clarify whether ISO 4762 product with matching material certification is acceptable — it nearly always is.
For engineers: New drawings should reference ISO 4762 (or DIN EN ISO 4762). Continuing to specify a withdrawn standard creates avoidable back-and-forth at the quoting stage.
For quality and documentation: Mill certificates and test reports from most manufacturers now reference ISO 4762. If your inspection documents must match the purchase order designation exactly, align the callout at order placement rather than at goods receipt.
The Bottom Line
DIN 912 and ISO 4762 are two designations for the same fastener, separated by standards history rather than engineering substance. Treat ISO 4762 as the current reference, accept DIN 912 as its legacy alias, and confirm certification wording early — that's all it takes to keep this classic cross-reference from slowing down a project.