About

About CacheLens

Turns a response's caching headers into a clear answer: cached or not, by whom, for how long, and what's wrong.

It parses Cache-Control, Expires, Date, Age, ETag, Last-Modified, Vary and Pragma and explains the browser and shared-cache outcome per RFC 9111. Runs in your browser; nothing is sent anywhere. It is a static read of the headers — real behavior also depends on method, status, and request headers.

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