The Timing-Allow-Origin response header specifies origins that are allowed to see values of attributes retrieved via features of the Resource Timing API, which would otherwise be reported as zero due to cross-origin restrictions.

Header type Response header
Forbidden header name no


Timing-Allow-Origin: *
Timing-Allow-Origin: <origin>[, <origin>]*


The server may specify "*" as a wildcard, thereby allowing any origin to see timing resources.
Specifies a URI that may see the timing resources. You can specify multiple origins, separated by commas.


To allow any resource to see timing resources:

Timing-Allow-Origin: *

To allow https://developer.mozilla.org to see timing resources, you can specify:

Timing-Allow-Origin: https://developer.mozilla.org


Specification Status Comment
Resource Timing Level 3
The definition of 'Timing-Allow-Origin' in that specification.
Editor's Draft Initial definition.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support Yes ? Yes ? Yes Yes
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes Yes ? Yes Yes Yes Yes

See also

Document Tags and Contributors

Contributors to this page: baileylo, chrisdavidmills
Last updated by: baileylo,