User Guide / Getting Started

Latency tests: what the number means and what counts as normal

Getting Started · Updated 2025-07-15 · ~2 min read

Clicking the lightning icon on a proxy group makes Clash fetch a test URL (default http://www.gstatic.com/generate_204) through every node in turn and record the full request time — that is the millisecond figure next to each node.

Reading the numbers

Low latency ≠ high speed

Latency measures responsiveness; bandwidth measures throughput. They are unrelated: a 60 ms node may be capped at 5 Mbps while a 220 ms node pushes 500 Mbps. Whether video stutters depends mostly on bandwidth — use the Benchmark page for a real download test ("Using Benchmark properly").

Also, one isolated timeout does not mean a node is dead — it may just be packet loss during the test. Test a couple more times before concluding.