ASTM / EN Grade Equivalent Finder
Type a grade or designation and read the equivalence records the material database holds for it — the designation systems, how close the match is, and what differs. Equivalents are a technical reference, not a substitution instruction.
Grade finder
Type a common grade (304, 316L, 6061), a UNS number (S31603), an EN number (1.4404) or an EN name (X2CrNiMo17-12-2).
What this calculates
A stainless steel grade travels under several names. The same austenitic grade a Saudi or American drawing calls 304 appears on a European mill certificate as 1.4301 or X5CrNi18-10, and in the Unified Numbering System as S30400. Aluminium and copper alloys do the same across AA, CDA, UNS and EN numbering. This finder resolves a designation in any of those systems to the grade record behind it and lists the published equivalence notes.
Each row you see is an approved record: the two grades, the designation systems on each side, a match type, and the reviewed wording that explains what the relationship is and where the two specifications part ways. The finder never says two grades are identical, because no two standards define a grade the same way — composition limits, mechanical minimums and test conditions all differ at the edges. Where the database has no approved record for a designation, the finder says so rather than guessing from the number pattern.
When a match matters for a live enquiry — a specification written to EN 10088 that must be supplied from ASTM A240 stock, or the other way round — send the result to our engineering desk. The enquiry opens pre-filled with the designation you searched and the rows you read, so the review starts from the same record.
Show how matches are found
How a match is found
- match = an Approved grade-equivalents row naming the grade (common designation, near comparable or similar family)
- no row → no match shown; a designation is never inferred from a number pattern
Every row shown comes from an approved record in the material database. Nothing is inferred from the designation itself.
The finder is a lookup, not a calculation. It reads the material database twice: once for every approved grade with its designation codes and search aliases, and once for every approved equivalence record. Your query is matched against the grade identifiers, common grades, aliases and codes — an exact designation ranks first, then a prefix, then a partial match — and the rows for the best five grades are returned.
A record renders only when both grades in it are approved. A pair whose counterpart is still under review stays out of the results until the reviewer publishes it, so the list you see can grow over time without any change to this page.
The match type is the reviewer's classification, shown verbatim: common designation, near comparable or similar family. The wording and the key difference come from the same record. Read the key difference before treating a match as interchangeable.
Frequently asked
- 01Is 304 the same as 1.4301?
- They are the common designations of the same austenitic grade in ASTM and EN, and the database records them as such — but the two standards set slightly different composition and mechanical limits. Check the key difference column and your project specification before substituting one for the other.
- 02Why does a grade I know show no result?
- Either the grade is not yet in the material database or its equivalence record has not passed review. Only approved records render publicly. Use the review request and our engineering desk will look at the designation against your specification.
- 03Which designation systems can I search?
- Common grade names, AISI and AA numbers, UNS numbers, EN material numbers and EN names, plus the search aliases recorded for each grade. Upper or lower case and surrounding spaces make no difference.
- 04Can I substitute a near-comparable grade on my project?
- Not on the strength of this page. A near-comparable match tells you where to start a review, and the key difference tells you what to check. Substitution is a decision for the specifier, made against the project specification.