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/HTTP

Timing-Allow-Origin

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

Syntax

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

Directives

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

Examples

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

Specifications

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

Browser compatibility

Feature	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari
Basic support	Yes	?	Yes	?	Yes	Yes