Timing-Allow-Origin header

The HTTP 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](https://developer.mozilla.org/en-US/docs/Glossary/Response%20header)

Syntax

Timing-Allow-Origin: *
Timing-Allow-Origin: <origin>, …, <originN>

Directives

• * (wildcard)
  • : Any origin may see timing resources.
• <origin>
  • : Specifies a URI that may see the timing resources. You can specify multiple origins, separated by commas.

Examples

Using Timing-Allow-Origin

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

Browser compatibility

See also

• Resource Timing API
• Server-Timing header
• Vary header