How to use CORS Header Checker
- Type or paste your text into CORS Header Checker's input area.
- Set Paste the response headers, Request origin, Request method so the output fits your use case.
- CORS Header Checker updates the output automatically as you type.
- Finish by choosing Copy to take the output with you.
About this tool
Everything CORS Header Checker does happens on your own device. CORS Header Checker handles your input locally and returns the result instantly, with no sign-up.
It is designed to do one job well and stay out of your way. No data is sent anywhere, so it stays fast and private by default.
Frequently asked questions
What is CORS Header Checker for?
Use CORS Header Checker to check your input without installing anything using the Paste the response headers, Request origin controls; everything happens client-side.
Does CORS Header Checker cost anything?
No — CORS Header Checker is completely free, with no sign-up and no hidden limits.
Where is my data processed by CORS Header Checker?
Entirely in your browser — CORS Header Checker keeps your data on your own machine and sends nothing anywhere.
Can I use CORS Header Checker without a connection?
Yes — after the first load CORS Header Checker runs entirely offline.