.js
5 claimants
2 primary
0 secondary
shared primary (2)
SWH popularity
Distinct files in the full Software Heritage archive (2026-06-04 export), dated by first appearance, following Desmazières, Di Cosmo, Lorentz (MSR 2025). Case-aggregated. citation.
1.4B
total files
736.7M
first seen 2021–2025 (52.8%)
2021
median year (half its files since)
Case variants in archive: .js (1.4B), .JS (79.2K), .Js (10.5K), .jS (244) — aggregated above.
Attribution status
This extension is attributed to JavaScript; JSFuck as primary by 4 authoritative claims.
Claimants (7)
Languages that list
.js among their extensions. Strength reflects whether the upstream source treated it as their primary extension.| Language | Source | Strength |
|---|---|---|
| JavaScript | linguist | primary |
| JavaScript | pygments | primary |
| JavaScript | wikidata | primary |
| JSFuck | wikidata | primary |
| JScript | wikipedia | proposed |
| JSFX | wikipedia | proposed |
| Source | wikipedia | proposed |
Wikidata says… (3)
File formats, image formats, audio codecs and other non-PL
entities that claim
.js 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.
| Format | Class (Wikidata P31) | Suggested label | MIME | Notes | Action |
|---|---|---|---|---|---|
| ExtendScript Q16976350 scripting language (an extension of JavaScript) and associated toolkit, developed by Adobe | programming language | — | — | — | Use as new PL ↗ |
| JavaScript Style Sheets Q1633849 Stylesheet language proposed by Netscape | style sheet language | — | text/javascript | — | Use as new PL ↗ |
| JavaScript format Q5924007 file format that contains scripts in JavaScript | file format | — | text/javascript | — | Use as new PL ↗ |
SWH-mined examples (0)
No archived examples for .js in our local mirror yet.