MIME Type Lookup

What is a MIME type?

MIME stands for Multipurpose Internet Mail Extensions. Originally designed for email attachments, MIME types are now the standard way browsers, servers, and APIs identify file formats. Every HTTP response includes a Content-Type header with the MIME type (e.g. Content-Type: application/json), telling the client how to interpret the data.

A MIME type has two parts: type/subtype. The type is the general category (text, image, audio, video, application, font, model, multipart) and the subtype is the specific format. Some include parameters — text/html; charset=utf-8 specifies both the format and character encoding. The application/octet-stream type is the fallback for unknown binary data, which browsers typically handle as a download.

Correct MIME types are essential for web development. If a CSS file is served as text/plain, browsers won’t apply the styles. If JavaScript is served with the wrong type, strict MIME checking (CORB) will block execution. Web servers like Nginx and Apache have built-in MIME type mappings, but when serving files from CDNs, object storage (S3), or custom APIs, you often need to set the Content-Type header manually.

Common MIME types