What is API Latency?

Learn what API latency is, how it's measured, what causes high latency, and how to optimize your API for faster response times.

API latency is the time delay between sending a request to an API and receiving a response. It includes DNS resolution, TCP connection, TLS handshake, server processing, and data transfer. Low latency means faster responses and better user experience. Our <a href="/api-checker">API latency checker</a> measures each component. Common causes of high latency include network distance, slow database queries, large payloads, and inefficient code.

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Millisecond-precision response times

DNS lookup & TTFB analysis

Support for all HTTP methods

Custom headers & body payloads

SSL certificate validation

Export results as JSON/CSV

Frequently Asked Questions

What is API latency measured in?

API latency is measured in milliseconds (ms). 1 second = 1000 milliseconds.

What causes high API latency?

Network distance, DNS resolution, TLS handshake, slow server processing, database queries, and large payloads.

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