CORS Header Generator

Build CORS response-header text locally and reject the invalid browser combination of wildcard origin with credentialed requests.

Allowed origin

Allowed methods

Allowed request headers

Exposed response headers

Preflight max-age seconds

Credentials Access-Control-Allow-Credentials: true

ReadyThese are response-header candidates for a server. They do not change browser CORS behavior until your server sends the appropriate values.

How to use this CORS Header Generator

Generate common Cross-Origin Resource Sharing response headers for a known origin and API policy. Enter your values above and the result is calculated directly in your browser. No account is required.

Fast answer, clear inputs

This tool is built around one job: give the answer quickly without forcing a signup or hiding the result. Related tools are linked nearby when the next calculation or conversion is useful.