](/en-US/docs/Glossary/Forbidden_header_name) |  no   
  
##  Syntax

http

    
    
    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
](https://searchfox.org/mozilla-
central/source/netwerk/protocol/http/nsCORSListenerProxy.cpp#1207) (86400
seconds). Chromium (prior to v76) [ caps at 10 minutes
](https://source.chromium.org/chromium/chromium/src/+/main:services/network/public/cpp/cors/preflight_result.cc;drc=52002151773d8cd9ffc5f557cd7cc880fddcae3e;l=36)
(600 seconds). Chromium (starting in v76) [ caps at 2 hours
](https://source.chromium.org/chromium/chromium/src/+/main:services/network/public/cpp/cors/preflight_result.cc;drc=49e7c0b4886cac1f3d09dc046bd528c9c811a0fa;l=31)
(7200 seconds). The default value is 5 seconds.

##  Examples

Cache results of a preflight request for 10 minutes:

http

    
    
    Access-Control-Max-Age: 600
    

##  Specifications

Specification  
---  
[ Fetch Standard  
#  http-access-control-max-age  ](https://fetch.spec.whatwg.org/#http-access-
control-max-age)  
  
##  Browser compatibility

BCD tables only load in the browser  with JavaScript enabled. Enable
JavaScript to view data.

##  See also

  * [ ` Access-Control-Allow-Headers ` ](/en-US/docs/Web/HTTP/Headers/Access-Control-Allow-Headers)
  * [ ` Access-Control-Allow-Methods ` ](/en-US/docs/Web/HTTP/Headers/Access-Control-Allow-Methods)

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