About Packet Loss Check

Packet Loss Check is a free packet loss test that measures loss, ping and jitter over real UDP, draws every packet on a timeline, and tells you in plain words what the result means for gaming, calls and streaming. It runs in your browser with no account, no download and nothing stored.

Why it exists

Most "internet tests" are speed tests. They measure how much data your line can carry for a few seconds, over TCP, which quietly resends anything that goes missing. That is the right tool for asking how fast a download will be, and the wrong one for asking why a call keeps freezing, because the thing that freezes calls, lost and late packets, is exactly what TCP hides.

The few tests that do measure packet loss mostly print one number and stop. A number alone does not tell you whether 2% loss is fine (for Netflix) or a disaster (for a ranked match), or whether it arrived as a steady trickle or one bad second. So this site shows the whole run, rates it separately for each use, and links the fix that matches the pattern it found.

How it measures

The test sends fifty 160-byte UDP packets a second through Cloudflare's TURN relay, using a WebRTC data channel that never retransmits. The relay runs in hundreds of cities, so your packets go to the nearest one and straight back, and the measurement reflects your own device, wifi, router and provider. The full method, including how each number is calculated and what the test cannot see, is on how this test works.

What it does not do

It does not measure download speed, and it cannot see beyond the nearest Cloudflare edge to a particular game server. It does not collect personal data: results are calculated in your browser and are not uploaded. Guides on the site explain causes and fixes in general terms; for a fault on your line, your provider is the one who can inspect it, and a copied test result is a good way to start that conversation.

Contact

Found a bug, or a result that looks wrong? Email hello@packetlosscheck.com.