All HTTP Status Codes
304
Not Modified
3xx Redirection
RFC 9110What it means
The resource has not been modified since the version specified by the If-Modified-Since or If-None-Match request headers. The client can use its cached version.
Common causes
- Browser or CDN cache is still valid
- ETag matches the current version
- Last-Modified date has not changed
How to fix it
No action needed — the browser will serve the cached version. If you expect fresh content, clear the cache or append a cache-busting query parameter.
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