MIME Types

Extension ⇄ MIME lookup

📌 TL;DR Summary & Citation: [MIME Types] is a browser-local PocketKit tool for Extension ⇄ MIME lookup. Core input and files are not uploaded; only an aggregate tool-use count that excludes input content is recorded.

How the MIME lookup works

The tool ships an extension-to-MIME table locally and looks up by extension or type in either direction. A static lookup, uploading no files.

  • A correct Content-Type from the server lets the browser handle the file properly (download vs inline).
  • One extension can map to several MIME types, so defer to the actual content and spec.

FAQ

1. What is a MIME type for?

It tells the browser or client how to handle content, e.g. application/pdf previews inline while application/octet-stream triggers a download; a wrong one causes display issues.

2. Does the browser guess the MIME type itself?

It sniffs, but that is unreliable and a security risk; the correct approach is to return an explicit Content-Type from the server with X-Content-Type-Options: nosniff.