MIME Type Finder

What the MIME Type Finder does

The MIME Type Finder looks up the correct MIME type for a given file extension or filename, giving you the exact Content-Type value a server or application should use for that file format.

How to use it

1. Enter a file extension or full filename.
2. The matching MIME type appears automatically.

Common uses

• Setting the correct Content-Type header when serving a file from a custom server.
• Checking what MIME type to configure for a file upload validation rule.
• Debugging a browser download or preview issue caused by an incorrect MIME type.
• Confirming the expected MIME type before writing a file-type detection function.
• Looking up a MIME type for an unfamiliar or less common file extension.

Good to know

Some file extensions map to more than one valid MIME type depending on context (like .js, which has historically used both text/javascript and application/javascript) — where more than one is in common use, it's worth checking current server or framework conventions rather than assuming a single universal answer.

MIME types (formally, "media types") exist because file extensions alone aren't a reliable way for software to know how to handle a file — the extension is just a naming convention, while the MIME type is what's actually communicated in HTTP headers and email attachments to tell a receiving system what kind of data it's dealing with, which is why getting it right matters for anything beyond just displaying a file locally.