Referer header
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The HTTPRefererrequest header contains the absolute or partial address from which a resource has been requested.TheReferer header allows a server to identify referring pages that people are visiting from or where requested resources are being used.This data can be used for analytics, logging, optimized caching, and more.
When you click a link, theReferer contains the address of the page that includes the link.When you make resource requests to another domain, theReferer contains the address of the page that uses the requested resource.
TheReferer header can contain anorigin,path, andquerystring, and may not containURL fragments (i.e.,#section) orusername:password information.The request'sreferrer policy defines the data that can be included. SeeReferrer-Policy for moreinformation andexamples.
TheReferer should also be sent in requests following aRefresh response (or equivalent<meta http-equiv="refresh" content="...">) that causes a navigation to a new page, if permitted by the referrer policy.
Note:The header name "referer" is actually a misspelling of the word "referrer".SeeHTTP referer on Wikipedia for more details.
Warning:This header may have undesirable consequences for user security and privacy.SeeReferer header: privacy and security concerns for more information and mitigation hints.
| Header type | Request header |
|---|---|
| Forbidden request header | Yes |
Syntax
Referer: <url>Directives
<url>An absolute or partial address of the web page that makes the request.URL fragments (i.e.,
#section) and user info (i.e.,username:passwordinhttps://username:password@example.com/foo/bar/) are not included.Origin, path, and query string may be included, depending on thereferrer policy.
Examples
Referer: https://developer.mozilla.org/en-US/docs/Web/JavaScriptReferer: https://example.com/page?q=123Referer: https://example.com/Specifications
| Specification |
|---|
| HTTP Semantics # field.referer |