cookies.

Servers will often produce this status if:

  * The [ ` Referer ` ](/en-US/docs/Web/HTTP/Headers/Referer) URL is too long 
  * There are too many [ Cookies ](/en-US/docs/Web/HTTP/Cookies) sent in the request 

##  Status

http

    
    
    431 Request Header Fields Too Large
    

##  Specifications

Specification  
---  
[ RFC 6585  
#  section-5  ](https://www.rfc-editor.org/rfc/rfc6585#section-5)  
  
##  See also

  * [ ` 414 URI Too Long ` ](/en-US/docs/Web/HTTP/Status/414)
  * [ Request header ](/en-US/docs/Glossary/Request_header)

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  *[
                
                 Non-standard
                
               ]: Non-standard. Check cross-browser support before using.
  *[
                
                 Deprecated
                
               ]: Deprecated. Not for use in new websites.
  *[
                
                 Experimental
                
               ]: Experimental. Expect behavior to change in the future.