.for

3 claimants 2 primary 1 secondary shared primary (2)

SWH popularity

From the SWH-MSR-ARV dataset (Desmazières, Di Cosmo, Lorentz, MSR 2025; file nb_extensions_alphanum.csv) — one row per (ext, year) in the full SWH archive. Case-aggregated. citation.

149.5K
total occurrences
32.4K
since 2019 (21.7%)
1972–2023
years active

Case variants in archive: .for (127.6K), .FOR (21.9K), .For (40), .foR (1) — aggregated above.

Attribution status

This extension is attributed to Formatted; fortran as primary by 2 authoritative claims.

Authoritative sources: ✓ Linguist ✗ Pygments · no claim ✓ Wikidata · Q83303 ✗ Wikipedia · no claim

Disagree or have a correction? Open a labelling issue.

Claimants (4)

Languages that list .for among their extensions. Strength reflects whether the upstream source treated it as their primary extension.
LanguageSourceStrength
Formattedlinguistprimary
fortranwikidataprimary
Forthlinguistsecondary
fortranlinguistsecondary

Wikidata says… (1)

File formats, image formats, audio codecs and other non-PL entities that claim .for on Wikidata (property P1195) or in the Wikipedia infobox. Source: data/derived/external_extension_index.csv. Click Use as new PL on any row to open the Add-PL form pre-filled with that entry's name, Wikipedia/Wikidata URL, and this extension — one submission creates the PL + claim.
Right entry isn't listed? Add manually ↗
FormatClass (Wikidata P31)Suggested labelMIMENotesAction
Fixed-format Fortran source Q111721131
file format
file formatUse as new PL ↗

Disambiguation rules (2)

Linguist heuristics that decide, by content, which language a .for file actually is.
RulePredictsKindPredicates (truncated)
h/linguist/.for/0Forthpredicates[{"kind": "any", "regexes": ["^: "]}]
h/linguist/.for/1fortranpredicates[{"kind": "any", "regexes": ["^(?i:[c*][^abd-z]| (subroutine|program|end|data)\\s|\\s*!)"]}]

SWH-mined examples (2)

Real archived programs with this extension, byte-verified against the SWH archive. Useful for deciding what this extension actually is when the attribution is uncertain.
FM251.FOR · 42384 B · seen 79× in SWH
predicted: fortran via heuristic
swh:1:cnt:26bb85f1f62268ad503835ca29a3321d542c13f1;origin=https://github.com/gklimowicz/FCVS;anchor=swh:1:rev:54136841d6a84c1e8403b9423b6ab0fbbb49d1e6;path=/FM251.FOR
Open in SWH · Raw bytes
FM254.FOR · 52590 B · seen 79× in SWH
predicted: fortran via heuristic
swh:1:cnt:7ecbaeb6ceb72c18f8f5b8a4660d36a8703937ba;origin=https://github.com/gklimowicz/FCVS;anchor=swh:1:rev:54136841d6a84c1e8403b9423b6ab0fbbb49d1e6;path=/FM254.FOR
Open in SWH · Raw bytes
Request more SWH-mined examples
If the examples above don't disambiguate what .for is, request a fresh mining run.
(or open the pre-filled issue directly)