CORS Debugging Guide for API Testing
CORS (Cross-Origin Resource Sharing) is a security feature that often blocks browser-based API tools. Our tester provides clear feedback, helping you identify when a server is missing the required headers.
When to use this solution:
Use this when your API requests work in cURL or Postman but fail with a 'Network Error' in our online tester.
Common Use Cases
- **Local Persistence:** Save your API requests in your browser storage for future debugging sessions.
- **Smart History:** Easily re-run previous requests that failed due to CORS issues.
- **CORS Feedback:** Get clear indicators when a request is blocked by browser security policies.
1Step-by-Step Guide
Identify the error
If you see a 'Network Error' after sending a request, open your browser's console (F12) to see if CORS is mentioned.
Check server headers
Ensure your API server sends the 'Access-Control-Allow-Origin' header, allowing requests from tektoolhub.com.
Verify OPTIONS method
If using custom headers, your server must also correctly handle the preflight OPTIONS request.
Retest the connection
Once headers are fixed on the server, try the request again in our tester to confirm success.
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Debug CORS NowFrequently Asked Questions
Why does it work in cURL but not here?
Browsers enforce CORS for security, while command-line tools like cURL do not. Your API needs to allow browser origins to work with web tools.
Can I bypass CORS?
The best way is to fix the server headers. For local development, you can use browser extensions that temporarily disable CORS.