Latency, ping and jitter, explained
Bandwidth is how much your connection can carry. Latency is how fast it responds. For everything interactive — clicks, calls, games — the second number is the one you feel.
The three numbers
Latency (or ping) is the time for a tiny message to reach a server and return — a round trip, measured in milliseconds. Jitter is how much that time varies between consecutive round trips. Loaded latency is your ping while the line is busy transferring data.
As a feel guide: under 20 ms is excellent, under 50 ms is good for everything including competitive gaming, 100 ms is noticeable in fast games and slightly delays every click, and 200+ ms makes conversation on calls awkward.
Why more Mbps does not fix lag
Bandwidth and latency are independent. A gigabit plan moves big files faster, but your click still needs a physical round trip to a server — and light in fiber covers only ~200 km per millisecond. Distance, routing and queuing set your ping; capacity does not.
This is why a 50 Mbps fiber line often feels snappier than gigabit cable, and why serious gamers care about the route to the game server more than the size of the pipe.
Jitter: the call killer
Real-time audio and video send a steady stream of small packets. If their travel time swings — 20 ms, then 80, then 35 — the receiver must buffer and guess, and you get robotic voices, frozen frames and "you go first" collisions.
Stable 60 ms latency usually makes for a better call than a connection that averages 30 ms but swings wildly. Wi-Fi interference and bufferbloat are the two most common sources of jitter at home.
The number most tests skip
Idle ping on a quiet line flatters your connection. The moment someone starts a download, oversized buffers in your modem or router can add hundreds of milliseconds — that is bufferbloat, and it is why calls stutter "even though the internet is fast".
Our test measures latency while the line is saturated in both directions and grades the result A–F. If you have ever wondered why evenings feel laggy on paper-fast internet, that grade is usually the answer.