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MIME Type Lookup

Look up the canonical MIME type for any extension, or work backwards.

Written by Golam Rabbani, Founder & Lead Engineer

Look up the canonical MIME (media) type for a file extension, or work backwards from a MIME type to common extensions. Data is sourced from the IANA media type registry plus widely-used vendor types, bundled with the page — no network calls.

Examples: webp · .pdf · application/json · image/

How to use this mime type lookup

  1. Type a file extension (e.g. webp, .pdf) or a full MIME type (e.g. image/png, application/json).
  2. Press Look up to search the bundled IANA reference table.
  3. Review every matching row — multiple matches are common (.jpg and .jpeg both map to image/jpeg).
  4. Use the Copy button on a row to put that MIME string on your clipboard.
  5. Need partial matches? Type a prefix like "image/" or "wo" — the tool returns every entry that starts with or contains your query.

About this mime type lookup

This lookup tool turns a file extension into its canonical MIME (media) type, or vice-versa, using a curated subset of the IANA media type registry plus widely-used vendor types (Office documents, archive formats, font formats, etc.). Each row tells you the extension, the MIME string, a short human-readable label, and whether the type is officially IANA-registered or just a common convention. The whole table ships with the page so lookups are instant and offline.

For example, querying "webp" returns one row: extension .webp · MIME image/webp · "WebP image" · IANA-registered. Querying "application/json" returns .json mapped to that exact type. Querying a prefix like "image/" returns every image entry in the table — useful when you are configuring an HTTP Accept header or a multer file filter and want to see what is available. Web developers use this to set correct `Content-Type` response headers, configure CDN caching rules per type, and write `accept` attributes on file inputs (e.g. `accept="image/png,image/jpeg,image/webp"`). Everything runs in your browser; no network call, no third-party API.

FAQ

Where does the data come from?
A curated subset of the official IANA media type registry plus widely-used vendor types (Microsoft Office, Apple disk images, etc.). Each row is flagged "Registered" if IANA lists it and "Common / unregistered" otherwise.
Why do some extensions map to multiple MIME types?
Most don't — but historically several types have changed (e.g. text/javascript and application/javascript were both valid for .js; WHATWG now mandates text/javascript). The tool shows every credible mapping in the table so you can pick the canonical one for your context.
Can I search by partial string?
Yes. If your query has no exact hit, the tool falls back to a substring/prefix search — e.g. "image/" lists every image type, "wo" lists .woff and .woff2.
Why is the MIME for .js text/javascript and not application/javascript?
Modern WHATWG and IANA guidance is text/javascript. application/javascript is still recognised by browsers but deprecated in the spec.
Is the list exhaustive?
No — IANA registers thousands of types. The table covers the ones you actually need day-to-day in web development, server configuration, and file handling. If a type is missing, fall back to the IANA registry online.