304 Not Modified
The HTTP 304 Not Modified client redirection response
code indicates that there is no need to retransmit the requested resources. It is an
implicit redirection to a cached resource. This happens when the request method is
a safe method, such as GET or HEAD,
or when the request is conditional and uses an If-None-Match or an
If-Modified-Since header.
The response must not contain a body and must include the headers that would
have been sent in an equivalent 200 OK response:
Cache-Control, Content-Location,
Date, ETag, Expires, and
Vary.
Note: Many developer tools' network panels
of browsers create extraneous requests leading to 304 responses, so that
access to the local cache is visible to developers.
Status
304 Not Modified
Specifications
| Specification |
|---|
| HTTP Semantics # status.304 |
Browser compatibility
BCD tables only load in the browser
Compatibility notes
- Browser behavior differs if this response erroneously includes a body on persistent connections. See 204 No Content for more detail.