304 Not Modified
The cached version of the resource is still valid, so no body is sent.
What it means
HTTP 304 Not Modified is a caching response. When a client makes a conditional request (using If-Modified-Since or If-None-Match) and the resource has not changed, the server returns 304 with no body, telling the client to use its cached copy.
When it happens
It happens on repeat visits when a browser or crawler revalidates cached assets and the server confirms nothing has changed since the last fetch.
How to fix it
- Nothing to fix — 304 is efficient, expected caching behaviour.
- If content changes are not appearing, check your ETag and Last-Modified headers are updating when content changes.
SEO impact
Positive. Correct 304 handling lets crawlers skip unchanged content, saving crawl budget and bandwidth so search engines spend their time on pages that actually changed.
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Related codes
The resource has permanently moved to a new URL.
302 FoundThe resource is temporarily at a different URL.
303 See OtherThe response to the request can be found at another URL using a GET request.
305 Use ProxyA deprecated code telling the client it must reach the resource through a specified proxy.
306 Switch ProxyA reserved, unused status code that no longer carries any meaning.
307 Temporary RedirectA temporary redirect that preserves the original request method.
Related guides
A plain-English primer on HTTP status codes for SEOs: what the 2xx, 3xx, 4xx, and 5xx families mean, which ones affect rankings, and the codes worth knowing.
How to find and fix broken linksA practical walkthrough for finding broken links on your site, working out why each one breaks, and fixing them so visitors and crawlers stop hitting dead ends.