Heroku Error Code Testing Dashboard

Warning: This page is for testing and learning purposes. Some actions will crash the app or cause timeouts. Use this only in development/testing environments.
H10

App Crashed

The application process crashed. This happens when your app exits unexpectedly due to an uncaught exception, memory issues, or calling process.exit().
H12

Request Timeout

HTTP request took longer than 30 seconds to complete. Heroku will return a 503 error to the client and terminate the request.
H14

No Web Dynos Running

No web dynos are running. This happens when all web dynos are scaled to 0 or have crashed and haven't been restarted yet.
R10

Boot Timeout

Web process failed to bind to PORT within 60 seconds of launch. This usually happens when your app takes too long to start or doesn't bind to the correct port.
R14

Memory Quota Exceeded

Process exceeded memory quota. This happens when your app uses more memory than allocated (512MB for Basic dynos).
CPU

High CPU Usage

Simulate high CPU usage that might cause performance issues and potential throttling.
How to View Logs:
• Real-time: heroku logs --tail -a ankit-github-demo-app
• Recent logs: heroku logs -a ankit-github-demo-app
• Filter by error: heroku logs --tail -a ankit-github-demo-app | grep -E "(H10|H12|H14|R10|R14)"
Recovery Actions:
App Crash (H10): Heroku automatically restarts. Check logs for root cause.
Timeout (H12): Page refresh is enough. Optimize slow endpoints.
No Dynos (H14): Scale up: heroku ps:scale web=1
Boot Timeout (R10): Fix startup issues and redeploy.
Memory (R14): Restart app: heroku restart and fix memory leaks.
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