MIME Type Lookup

How MIME Type Lookup works

Find the MIME type for a file extension, or the extensions for a MIME type, across images, fonts, documents and archives. Everything happens inside this page: the tool reads your input, runs the calculation or conversion locally, and hands the result back to you. Nothing is transmitted, because there is no backend to transmit it to.

That design choice is deliberate. Most free tool sites upload your files to a server, process them there, and quietly keep a copy. Toolcin cannot do that — the site is a set of static files. If your connection dropped the moment the page finished loading, every tool would still work.

Extension to type, and back

Search by extension to get the Content-Type a server should send, or search by type to see the extensions it covers. The table covers the formats web servers actually serve: HTML, CSS, JavaScript, JSON, images, fonts, documents and archives.

A wrong Content-Type is the classic cause of a stylesheet that loads but does not apply — the browser refuses to execute CSS served as text/plain.

The ones people get wrong

JavaScript is text/javascript in the current standard (application/javascript is legacy but still accepted). SVG must be image/svg+xml, not image/svg. WOFF2 is font/woff2, and JSON is application/json with no charset parameter needed — it is always UTF-8.

Where the header matters

Uploads that are validated by MIME type rather than extension, APIs that reject a request with the wrong Content-Type, and static hosts that guess from the extension — sometimes wrongly for newer formats.

Good to know

• Works offline once loaded, including on flights and in locked-down networks.
• No file size limit beyond your device's own memory.
• Free to use, with no account and no usage counter.
• Results are produced locally, so they are not logged or shared with anyone.

Questions