304 Not Modified

What it means

Returned for conditional requests with If-None-Match (ETag) or If-Modified-Since. The browser reuses its cached version, saving bandwidth.

Common causes

• The browser revalidated a cached resource and it has not changed.

How to fix it

1. No fix needed; it is a caching success.
2. If users see stale content, review ETag and Cache-Control settings.

Example response

HTTP/1.1 304 Not Modified
ETag: "v3"

Worked example

A client requests an old URL and receives a redirect with a Location header. It requests the destination next, preserving or changing the HTTP method according to the specific redirect code.

How to read this response

1. Find the status line in your browser's Network panel, API client, or server access log.
2. Read the response body and headers shown above; headers such as Location, Allow, Retry-After, and WWW-Authenticate explain the next step.
3. Use the code's class to orient your diagnosis: informational, successful, redirected, request-related, or server-side.

How to check a status code

Enter a URL in the HTTP Status Checker to see its status code, every redirect hop, and response time. For redirect-heavy pages, the Website Speed Test shows how much time redirects add.

Frequently asked questions

What it means: HTTP 304

304 Not Modified: The cached copy is still valid, so the server sends no body.

Common causes: 304

The browser revalidated a cached resource and it has not changed.

How to fix it: HTTP 304

No fix needed; it is a caching success. If users see stale content, review ETag and Cache-Control settings.

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