3xx Redirects

304 Not Modified

The browser's cached copy is still current, so the server sends no body. This saves bandwidth.

When you see it

The browser sent If-None-Match (ETag) or If-Modified-Since and the resource did not change.

1
Nothing to fix; it is a good sign that caching works.
2
If users see stale CSS or JS after a deploy, use versioned file names (Vite's build does this) instead of turning caching off.

The first line of the response shows the status code; -L follows redirects and shows each step.

curl -I https://example.com/page
curl -IL https://example.com/old-page

What does HTTP 304 mean?

The browser's cached copy is still current, so the server sends no body. This saves bandwidth.

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