MIME Types Reference

MIME (Multipurpose Internet Mail Extensions) types identify the format of files and data transmitted over the internet. Originally designed for email attachments, MIME types are now used everywhere: HTTP Content-Type headers tell browsers how to handle response data, web servers determine file handling based on extensions mapped to MIME types, and file upload validation uses MIME types to verify submitted file formats. A MIME type consists of a type and subtype separated by a slash: text/html for HTML documents, application/json for JSON data, image/png for PNG images, video/mp4 for MP4 video. Common categories include: text/* (html, css, javascript, plain, xml), application/* (json, pdf, zip, octet-stream), image/* (jpeg, png, webp, svg+xml, gif), audio/* (mpeg, ogg, wav), video/* (mp4, webm), and font/* (woff2, woff, ttf). The AllTools MIME Type lookup provides instant search across hundreds of MIME types — enter a file extension to find its MIME type, or search by MIME type to find associated extensions. This reference is essential for: configuring web server Content-Type headers, setting correct MIME types in API responses, validating file uploads, and debugging browser rendering issues caused by incorrect MIME types. All lookup runs locally in your browser.

Correct MIME type usage prevents numerous web development issues. Browsers use Content-Type headers to determine how to process responses — serving JavaScript with text/html instead of application/javascript causes parsing failures. The X-Content-Type-Options: nosniff security header prevents browsers from MIME-sniffing (guessing the type from content rather than trusting the header), making correct MIME types essential for security. Server configuration files (Apache's mime.types, Nginx's mime.types) map file extensions to MIME types for static file serving. Service workers and PWAs must return the correct MIME types for cached resources. Canvas element's toBlob() and toDataURL() methods accept MIME type parameters (image/png, image/jpeg, image/webp) to control output format. Fetch API and XMLHttpRequest use Content-Type headers to indicate request body format — application/json for JSON payloads, multipart/form-data for file uploads, application/x-www-form-urlencoded for form submissions. Email attachments use MIME types to indicate how receiving email clients should handle attached files. The AllTools MIME reference helps developers quickly look up the correct type for any file format without searching through documentation or server configuration files.