Network quality
Latency Test
Latency is the time a packet takes to travel to a server and back. This site reports round-trip latency because browser clocks and server clocks are not synchronized.
Run the packet loss testRound-trip time
Version one reports round-trip time: the time between sending a test packet and receiving its echo back from the test server.
Why latency changes
Routing, Wi-Fi signal, local congestion, VPNs, and server distance can all change packet timing during a test.