MIME Type Lookup

Look up MIME types by file extension or find extensions for any MIME type. 200+ types covered.

File Extension
Type a file extension to look up its MIME type.

What Are MIME Types?

MIME types (Multipurpose Internet Mail Extensions) are standardized identifiers used to describe the nature and format of data. Originally defined for email attachments, MIME types are now central to the web — they appear in the Content-Type HTTP header, HTML <link> and <script> tags, and file upload validation. Every MIME type follows the pattern type/subtype, optionally followed by parameters like ; charset=utf-8.

MIME Type Categories

  • image/* — image/jpeg, image/png, image/webp, image/svg+xml, image/gif, image/avif
  • audio/* — audio/mpeg (MP3), audio/ogg, audio/wav, audio/flac, audio/aac
  • video/* — video/mp4, video/webm, video/ogg, video/quicktime
  • text/* — text/html, text/css, text/javascript, text/csv, text/plain, text/xml
  • application/* — application/json, application/pdf, application/zip, application/wasm, application/octet-stream
  • font/* — font/woff2, font/woff, font/ttf, font/otf
  • multipart/* — multipart/form-data, multipart/mixed

Content-Type Header

Servers set the Content-Type response header to tell browsers how to handle the response body. If a server sends a JavaScript file with Content-Type: text/plain, the browser will display it as text rather than execute it. Getting the Content-Type right is essential for security — sending HTML with the wrong MIME type and without X-Content-Type-Options: nosniff can enable MIME-sniffing attacks. Use our HTTP Header Inspector to check headers on any response.

MIME Types for Web Assets

Common web asset MIME types and their correct values:

  • HTML: text/html; charset=utf-8
  • CSS: text/css
  • JavaScript: text/javascript (the official type; application/javascript is also accepted)
  • JSON: application/json
  • WebAssembly: application/wasm
  • SVG: image/svg+xml
  • Web fonts: font/woff2, font/woff
  • Source maps: application/json

Binary vs. Text MIME Types

MIME types can be classified as binary or text. Text types (text/html, text/css, application/json) contain human-readable characters and should be served with a charset parameter. Binary types (image/jpeg, audio/mpeg, application/pdf) contain raw byte data that should not be modified by line-ending normalization. When serving files, always use the correct binary/text classification to avoid data corruption. The application/octet-stream type is a safe default for unknown binary data and causes browsers to trigger a download rather than attempting to display the content.

Frequently Asked Questions

A MIME type is a standardized identifier for the type and format of data, used in HTTP headers, email, and HTML. It follows the format type/subtype (e.g., image/jpeg, text/html). Servers send MIME types in the Content-Type header so browsers know how to process the response.
The official IANA-registered MIME type for JSON is application/json. The application prefix indicates it is a structured data format for machine consumption. While text/json may work in some contexts, application/json is the correct and universally recognized type.
For unknown binary files, use application/octet-stream. For HTML forms, use enctype="multipart/form-data". For specific file types, use the correct MIME type: image/jpeg for JPEGs, application/pdf for PDFs, etc.
The charset parameter specifies the character encoding for text-based responses. Content-Type: text/html; charset=utf-8 means the HTML is UTF-8 encoded. Always include charset=utf-8 for text/html, text/css, application/javascript, and application/json to avoid garbled characters.
The correct MIME type for WebP images is image/webp. WebP is a modern format from Google offering superior compression over JPEG and PNG, with support for transparency and animation. Most modern web servers automatically serve the correct MIME type for .webp files.