Basics | 4 min read

What is packet loss and how to spot it

Everything you send online is split into small packets. Packet loss is the percentage of those packets that never arrive. A little is normal on some networks; a lot makes connections stutter, freeze and drop.

How it feels

Web pages and downloads recover quietly because the missing packets are simply sent again, so you notice slowness rather than errors. Real-time apps cannot wait, so lost packets appear as glitchy audio, frozen video or rubber-banding in games.

How much is too much?

Ideally zero. Around 1 percent starts to affect voice and video, and 2 to 5 percent makes real-time apps frustrating. Persistent loss above that usually signals a real fault.

What a website can and cannot measure

Browsers cannot send the raw packets needed to count true packet loss, and the TCP protocol used for web traffic hides loss by resending data. So WiFi Ping reports the share of small latency probes that failed or timed out. That is not identical to packet loss, but repeated failures are a reliable warning sign that something is wrong.

Typical causes and fixes

Weak Wi-Fi, interference and overloaded routers are the most common causes at home, and they are easy to test: repeat the test next to the router or with a cable. If loss disappears, the problem is your Wi-Fi. If it persists across connections and times of day, contact your provider with your saved test results.

  • Move closer to the router or switch to Ethernet
  • Restart the router and modem
  • Check for damaged cables
  • Try a different Wi-Fi band
  • Contact your provider if it continues