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


Resource Timing Level 2 (Resource Timing 2)
# sec-timing-allow-origin

Browser compatibility

BCD tables only load in the browser

See also