Referrer-Policy
Referrer-Policy
The Referrer-Policy HTTP 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 |
|---|---|
| Forbidden header name | no |
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 original header name Referer is a misspelling of the word "referrer". The Referrer-Policy header does not share this misspelling.
Directives
no-referrer-
The
Refererheader will be omitted: sent requests do not include any referrer information. no-referrer-when-downgrade-
Send the origin, path, and querystring in
Refererwhen the protocol security level stays the same or improves (HTTP→HTTP, HTTP→HTTPS, HTTPS→HTTPS). Don't send theRefererheader for requests to less secure destinations (HTTPS→HTTP, HTTPS→file). origin-
Send only the origin in the
Refererheader. For example, a document athttps://example.com/page.htmlwill send the referrerhttps://example.com/. origin-when-cross-origin-
When performing a same-origin request to the same protocol level (HTTP→HTTP, HTTPS→HTTPS), 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
Refererheader for cross-origin requests. strict-origin-
Send only the origin when the protocol security level stays the same (HTTPS→HTTPS). Don't send the
Refererheader to less secure destinations (HTTPS→HTTP). -
strict-origin-when-cross-origin(default) -
Send the origin, path, and querystring 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
Refererheader 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">
Alternatively, you can set a noreferrer link relation on an a, area, or link elements:
<a href="http://example.com" rel="noreferrer">
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 aReferrer-PolicyHTTP header on the CSS stylesheet's response. - For
<style>elements orstyleattributes, the owner document's referrer policy is used.
Examples
no-referrer
| From document | Navigation to | Referrer used |
|---|---|---|
| https://example.com/page | anywhere | (no referrer) |
no-referrer-when-downgrade
| From document | Navigation to | Referrer used |
|---|---|---|
| https://example.com/page | https://example.com/otherpage | https://example.com/page |
| https://example.com/page | https://mozilla.org | https://example.com/page |
| https://example.com/page | http://example.com | (no referrer) |
origin
| From document | Navigation to | Referrer used |
|---|---|---|
| https://example.com/page | anywhere | https://example.com/ |
origin-when-cross-origin
| From document | Navigation to | Referrer used |
|---|---|---|
| https://example.com/page | https://example.com/otherpage | https://example.com/page |
| https://example.com/page | https://mozilla.org | https://example.com/ |
| https://example.com/page | http://example.com/page | https://example.com/ |
same-origin
| From document | Navigation to | Referrer used |
|---|---|---|
| https://example.com/page | https://example.com/otherpage | https://example.com/page |
| https://example.com/page | https://mozilla.org | (no referrer) |
strict-origin
| From document | Navigation to | Referrer used |
|---|---|---|
| https://example.com/page | https://mozilla.org | https://example.com/ |
| https://example.com/page | http://example.com | (no referrer) |
| http://example.com/page | anywhere | http://example.com/ |
strict-origin-when-cross-origin
| From document | Navigation to | Referrer used |
|---|---|---|
| https://example.com/page | https://example.com/otherpage | https://example.com/page |
| https://example.com/page | https://mozilla.org | https://example.com/ |
| https://example.com/page | http://example.com | (no referrer) |
unsafe-url
| From document | Navigation to | Referrer used |
|---|---|---|
| https://example.com/page?q=123 | anywhere | https://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(andnetwork.http.referer.defaultPolicy.pbmodefor 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
| Specification |
|---|
| Referrer Policy # referrer-policy-header |
Browser compatibility
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
Referrer-Policy |
56 |
79 |
50 |
No |
43 |
11.1 |
56 |
56 |
50 |
43 |
No |
7.2 |
default_strict-origin-when-cross-origin |
85 |
85 |
87 |
No |
71 |
No |
85 |
85 |
87 |
60 |
No |
14.0 |
same-origin |
61 |
79 |
52 |
No |
48 |
11.1 |
61 |
61 |
52 |
45 |
No |
7.2 |
strict-origin |
61 |
79 |
52 |
No |
48 |
11.1 |
61 |
61 |
52 |
45 |
No |
7.2 |
strict-origin-when-cross-origin |
61 |
79 |
52 |
No |
48 |
11.1 |
61 |
61 |
52 |
45 |
No |
7.2 |
See also
- Web security > Referer header: privacy and security concerns
- HTTP referer on Wikipedia
- When using Fetch:
Request.referrerPolicy - The obsolete
Content-Security-Policy'sreferrerdirective. - Same-origin policy
- Tighter Control Over Your Referrers – Mozilla Security Blog
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https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referrer-Policy