Packet Loss

Data travels in small packets. Packet loss is the share that never arrives. Ping and MTR measure it as the share of probes that got no answer.

How much is too much

• 0%: what a healthy connection shows almost all the time.
• 1 to 2%: you’ll notice it in calls and games, as glitches and rubber-banding.
• Over 5%: pages stall and calls break up.

Loss in bursts, several in a row, is a short dropout. Netutilus draws lost probes in red on its charts, so bursts stand out from scattered losses.

Real loss and router deprioritising

Routers on the internet forward your traffic first, and answer probes addressed to themselves last, if at all. So a router in the middle of a path can show loss while the hosts behind it show none: your traffic passed through untouched.

Only loss that continues to the destination is real. That’s the first rule of reading MTR.

Where it comes from

• At hop 1 or 2: your Wi-Fi, a faulty cable, or the router. Try a cable, or another one.
• Starting at a hop in your provider’s network: their link or equipment. MTR’s history is the evidence to send them.
• On Wi-Fi only: interference or a weak signal. See Wi-Fi Analyzer.

Related

• Latency and Jitter.
• The internet is slow or keeps dropping.