API Latency Checker
Free API latency checker tool. Measure your API response times, DNS lookup, TTFB, and total latency. Test REST, GraphQL, and WebSocket endpoints instantly.
Our API latency checker provides detailed insights into your API performance. Measure DNS lookup times, Time to First Byte (TTFB), total response time, and more. Test any HTTP method including GET, POST, PUT, DELETE, and PATCH with custom headers and body payloads.
Frequently Asked Questions
What is API latency?
API latency is the time it takes for a request to travel from the client to the server and back. It includes DNS lookup, connection time, TTFB, and content download time.
What is a good API response time?
A good API response time is under 200ms. Under 100ms is excellent, 200-500ms is acceptable, and anything over 1000ms needs optimization.
How do you measure API latency?
We measure DNS lookup time, TCP connection time, TLS handshake time, Time to First Byte (TTFB), and total response time from request to full response.
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