Network & API

How to Test CORS Configuration

Step-by-step guide to checking whether an API endpoint is configured to allow cross-origin requests using the DevHexLab CORS Tester.

Tool Used

CORS Header Tester

Open tool
1

Open the CORS Tester

Navigate to /tools/network/cors-tester.

2

Enter the API URL

Type the full URL of the API endpoint you want to test for CORS support.

3

Set the origin

Enter the origin URL that would be making the cross-origin request (for example, https://yourfrontend.com). The tool sends a preflight OPTIONS request from this origin.

4

Read the result

The tool shows whether the server returns the correct Access-Control-Allow-Origin header and whether the preflight request succeeds.

All done!

You are ready to use CORS Header Tester like a pro.

Try it now
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