Redirection

304 304 Not Modified

The file has not changed since the browser last fetched it, so the server sends headers only and the browser reuses its cached copy. Seeing plenty of these is a sign caching is working.

Common causes

  • Normal, healthy caching behaviour.

How to fix it

  • If you never see 304s, your server may not be sending ETag or Last-Modified headers, and returning full responses when it does not need to.

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