Free online API response time tester. Test multiple API endpoints with concurrent requests, latency analysis, and CSV export. Runs entirely in your browser — no signup required.
Zero Dependencies · Works OfflineAPI Response Time Tester
Enter API endpoint URLs (one per line), click Start Test. Supports HTTP/HTTPS, concurrent requests, real-time latency, status code and response body size.
FAQ
Is this tool free?
Yes, completely free with no signup or login required.
Will my data be uploaded to a server?
No. All testing runs locally in your browser — nothing is uploaded to any server.
About API Response Time Tester
Free online API response time tester. Batch test multiple endpoints, concurrent requests, latency analysis, export CSV report. Pure client-side.
API Response Time Tester | No Signup Required · Data stays in your browser
Feedback: dexshuang@google.com