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http header

Referrer-Policy header

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The HTTP Referrer-Policy response header controls how much referrer information (sent with the Referer header) should be included with requests. Aside from the HTTP header, you can set this policy in HTML.

Header type [Response header](https://developer.mozilla.org/en-US/docs/Glossary/Response%20header)

Syntax

Referrer-Policy: no-referrer
Referrer-Policy: no-referrer-when-downgrade
Referrer-Policy: origin
Referrer-Policy: origin-when-cross-origin
Referrer-Policy: same-origin
Referrer-Policy: strict-origin
Referrer-Policy: strict-origin-when-cross-origin
Referrer-Policy: unsafe-url

[!NOTE] The header name Referer is a misspelling of the word “referrer”. The Referrer-Policy header does not share this misspelling.

Directives

  • no-referrer

    • : The Referer header will be omitted: sent requests do not include any referrer information.

  • no-referrer-when-downgrade

    • : Send the origin, path, and query string in Referer when the protocol security level stays the same or improves (HTTP→HTTP, HTTP→HTTPS, HTTPS→HTTPS). Don’t send the Referer header for requests to less secure destinations (HTTPS→HTTP, HTTPS→file).

  • origin

    • : Send only the origin in the Referer header. For example, a document at https://example.com/page.html will send the referrer https://example.com/.

  • origin-when-cross-origin

    • : When performing a same-origin request, send the origin, path, and query string. Send only the origin for cross origin requests and requests to less secure destinations (HTTPS→HTTP).

  • same-origin

    • : Send the origin, path, and query string for same-origin requests. Don’t send the Referer header for cross-origin requests.

  • strict-origin

    • : Send only the origin when the protocol security level stays the same (HTTPS→HTTPS). Don’t send the Referer header to less secure destinations (HTTPS→HTTP).

  • strict-origin-when-cross-origin (default)

    • : Send the origin, path, and query string when performing a same-origin request. For cross-origin requests send the origin (only) when the protocol security level stays same (HTTPS→HTTPS). Don’t send the Referer header to less secure destinations (HTTPS→HTTP).

      [!NOTE] This is the default policy if no policy is specified, or if the provided value is invalid (see spec revision November 2020). Previously the default was no-referrer-when-downgrade.

  • unsafe-url

    • : Send the origin, path, and query string when performing any request, regardless of security.

      [!WARNING] This policy will leak potentially-private information from HTTPS resource URLs to insecure origins. Carefully consider the impact of this setting.

Integration with HTML

You can also set referrer policies inside HTML. For example, you can set the referrer policy for the entire document with a <meta> element with a name of referrer:

<meta name="referrer" content="origin" />

You can specify the referrerpolicy attribute on <a>, <area>, <img>, <iframe>, <script>, or <link> elements to set referrer policies for individual requests:

<a href="http://example.com" referrerpolicy="origin">…</a>

Alternatively, you can set a noreferrer link relation on an a, area, or link elements:

<a href="http://example.com" rel="noreferrer">…</a>

[!WARNING] As seen above, the noreferrer link relation is written without a dash. When you specify the referrer policy for the entire document with a <meta> element, it should be written with a dash: <meta name="referrer" content="no-referrer">.

Integration with CSS

CSS can fetch resources referenced from stylesheets. These resources follow a referrer policy as well:

  • External CSS stylesheets use the default policy (strict-origin-when-cross-origin), unless it’s overwritten by a Referrer-Policy HTTP header on the CSS stylesheet’s response.
  • For <style> elements or style attributes, the owner document’s referrer policy is used.

Examples

no-referrer

From documentNavigation toReferrer used
https://example.com/pageanywhere(no referrer)

no-referrer-when-downgrade

From documentNavigation toReferrer used
https://example.com/pagehttps://example.com/otherpagehttps://example.com/page
https://example.com/pagehttps://mozilla.orghttps://example.com/page
https://example.com/pagehttp://example.com(no referrer)
http://example.com/pageanywherehttp://example.com/page

origin

From documentNavigation toReferrer used
https://example.com/pageanywherehttps://example.com/

origin-when-cross-origin

From documentNavigation toReferrer used
https://example.com/pagehttps://example.com/otherpagehttps://example.com/page
https://example.com/pagehttps://mozilla.orghttps://example.com/
https://example.com/pagehttp://example.com/pagehttps://example.com/

same-origin

From documentNavigation toReferrer used
https://example.com/pagehttps://example.com/otherpagehttps://example.com/page
https://example.com/pagehttps://mozilla.org(no referrer)

strict-origin

From documentNavigation toReferrer used
https://example.com/pagehttps://mozilla.orghttps://example.com/
https://example.com/pagehttp://example.com(no referrer)
http://example.com/pageanywherehttp://example.com/

strict-origin-when-cross-origin

From documentNavigation toReferrer used
https://example.com/pagehttps://example.com/otherpagehttps://example.com/page
https://example.com/pagehttps://mozilla.orghttps://example.com/
https://example.com/pagehttp://example.com(no referrer)

unsafe-url

From documentNavigation toReferrer used
https://example.com/page?q=123anywherehttps://example.com/page?q=123

Specify a fallback policy

If you want to specify a fallback policy in case the desired policy hasn’t got wide enough browser support, use a comma-separated list with the desired policy specified last:

Referrer-Policy: no-referrer, strict-origin-when-cross-origin

In the above scenario, no-referrer is used only if the browser does not support the strict-origin-when-cross-origin policy.

[!NOTE] Specifying multiple values is only supported in the Referrer-Policy HTTP header, and not in the referrerpolicy attribute.

Browser-specific preferences/settings

Firefox preferences

You can configure the default referrer policy in Firefox preferences. The preference names are version specific:

  • Firefox version 59 and later: network.http.referer.defaultPolicy (and network.http.referer.defaultPolicy.pbmode for private networks)
  • Firefox versions 53 to 58: network.http.referer.userControlPolicy

All of these settings take the same set of values: 0 = no-referrer, 1 = same-origin, 2 = strict-origin-when-cross-origin, 3 = no-referrer-when-downgrade.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also