CORS Header Generator
Build explicit CORS response headers for an API or web resource.
Configure cross-origin access deliberately
CORS grants browser-based JavaScript permission to read selected cross-origin responses. It is not an authentication mechanism or a server-to-server access control.
Never combine a wildcard origin with credentials, and vary cached responses by Origin when returning origin-specific access headers.
How to use the CORS Header Generator
- Complete the available options using values appropriate for your project.
- Generate the result and read it before copying or downloading it.
- Test the generated output in a safe environment before production use.
Practical example
Review the result against the needs of the specific website or account instead of treating a generated value as a complete security review.
What this tool cannot guarantee
A focused browser tool cannot replace layered security controls, current software, monitoring or a professional assessment.
Continue this workflow with the HTTP Security Headers Checker
Frequently asked questions
Is the CORS Header Generator free to use?
Yes. It is available without an account or paid subscription.
Is my input uploaded or stored?
The core operation runs in your browser. Avoid pasting secrets into any web page unless the individual tool explicitly explains how the data is handled.
Should I review the result before using it?
Yes. Check the output for your project and test it in the intended environment before production use.