Access-Control-Max-Age
The 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 |
|---|---|
| Forbidden header name | no |
Syntax
Access-Control-Max-Age: <delta-seconds>
Directives
- <delta-seconds>
-
Maximum number of seconds 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 Standard # http-access-control-max-age |
Browser compatibility
BCD tables only load in the browser