Headers: Access-Control-Max-Age
Access-Control-Max-Age header
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The HTTP Access-Control-Max-Age response header indicates how long the results of a preflight request (that is, the information contained in the Access-Control-Allow-Methods and Access-Control-Allow-Headers headers) can be cached.
| Header type | Response header |
|---|
Syntax
Access-Control-Max-Age: <delta-seconds>
Directives
<delta-seconds>-
Maximum number of seconds for which the results can be cached as an unsigned non-negative integer. Firefox caps this at 24 hours (86400 seconds). Chromium (prior to v76) caps at 10 minutes (600 seconds). Chromium (starting in v76) caps at 2 hours (7200 seconds). The default value is 5 seconds.
Examples
Cache results of a preflight request for 10 minutes:
Access-Control-Max-Age: 600
Specifications
| Specification |
|---|
| Fetch> # http-access-control-max-age> |
Browser compatibility
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
Access-Control-Max-Age |
4 | 12 | 3.5 | 12 | 4 | 18 | 4 | 12 | 3.2 | 1.0 | 2 | 3.2 |
See also
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https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/Access-Control-Max-Age
