What does HTTP/1.1 302 mean exactly?

Question

Some article I read once said that it means jumping (from one URI to another), but I detected this "302" even when there was actually no jumping at all!

Answer 1

According to RFC 1945/Hypertext Transfer Protocol - HTTP / 1.0:

   302 Moved Temporarily

   The requested resource resides temporarily under a different URL.
   Since the redirection may be altered on occasion, the client should
   continue to use the Request-URI for future requests.

   The URL must be given by the Location field in the response. Unless
   it was a HEAD request, the Entity-Body of the response should
   contain a short note with a hyperlink to the new URI(s).

   If the 302 status code is received in response to a request using
   the POST method, the user agent must not automatically redirect the
   request unless it can be confirmed by the user, since this might
   change the conditions under which the request was issued.

       Note: When automatically redirecting a POST request after
       receiving a 302 status code, some existing user agents will
       erroneously change it into a GET request.

Answer 2

A 302 redirect means that the page was temporarily moved, while a 301 means that it was permanently moved.

301s are good for SEO value, while 302s aren't because 301s instruct clients to forget the value of the original URL, while the 302 keeps the value of the original and can thus potentially reduce the value by creating two, logically-distinct URLs that each produce the same content (search engines view them as distinct duplicates rather than a single resource with two names).

Answer 3

Since June 2014 the RFC 2616 is obsolete and must not be used as reference anymore. The RFC 7231 is the current reference for the semantics and content of the HTTP/1.1 protocol.

A response with 302 is a common way of performing URL redirection. Along with the 302 status code, the response should include a Location header with a different URI. Such header will be read by the user agent and then perform the redirection:

Web browsers may change from POST to GET in the subsequent request. If this behavior is undesired, the 307 (Temporary Redirect) status code can be used instead.

This is how the 302 status code is defined in the RFC 7231:

6.4.3. 302 Found

The 302 (Found) status code indicates that the target resource resides temporarily under a different URI. Since the redirection might be altered on occasion, the client ought to continue to use the effective request URI for future requests.

The server SHOULD generate a Location header field in the response containing a URI reference for the different URI. The user agent MAY use the Location field value for automatic redirection. The server's response payload usually contains a short hypertext note with a hyperlink to the different URI(s).

Note: For historical reasons, a user agent MAY change the request method from POST to GET for the subsequent request. If this behavior is undesired, the 307 (Temporary Redirect) status code can be used instead.

According to MDN web docs from Mozilla, a typical use case for 302 is:

The Web page is temporarily not available for reasons that have not been unforeseen. That way, search engines don't update their links.

Other status codes for redirection

The RFC 7231 defines the following status codes for redirection:

• 301 (Moved Permanently)
• 302 (Found)
• 307 (Temporary Redirect)

The RFC 7238 was created to define another status code for redirection:

• 308 (Permanent Redirect)

Refer to this answer for further details.

Answer 4

As per the http status code definitions a 302 indicates a (temporary) redirect. "The requested resource resides temporarily under a different URI"

Answer 5

In the term of SEO , 301 and 302 both are good it is depend on situation,

If only one version can be returned (i.e., the other redirects to it), that’s great! This behavior is beneficial because it reduces duplicate content. In the particular case of redirects to trailing slash URLs, our search results will likely show the version of the URL with the 200 response code (most often the trailing slash URL) -- regardless of whether the redirect was a 301 or 302.

Answer 6

From Wikipedia:

The HTTP response status code 302 Found is the most common way of performing a redirection. It is an example of industrial practice contradicting the standard.