Packet loss test
Checks whether packets between your browser and our test node arrive, and how many come back too late to be useful. Then run an ICMP echo from our server to any public host for raw loss.
"Test under load" adds short download and upload bursts to show bufferbloat.
Latency trace
Teal is idle, amber is under load, red marks a packet with no reply.
Distribution
How often each round-trip time occurred.
The distribution appears after the first test.
Diagnostics from Chicago (US)
These tests run from our test node in Chicago (US), not from your browser. Use them to check whether a host is reachable and how far it is from a US Midwest network. Private and internal addresses can't be tested.
Two ways this page measures loss
The browser tests send small timestamped messages over a WebSocket to our test node in Chicago (US) and time each reply. Because a WebSocket runs over TCP, a lost packet is retransmitted rather than vanishing, so it shows up as a late reply; anything that takes longer than two seconds is counted as lost. For raw ICMP loss from a server, use the network echo test further down the page.
The network echo test sends real ICMP echo requests from our server and reports exactly how many replies came back. Use it to check whether a website, game server or office router is dropping packets, independent of your own connection.
How much packet loss is acceptable?
On a wired connection, any loss is a sign of a problem. Around 1% is noticeable in calls and games; above 2 to 3%, calls break up and games rubber-band. Short bursts of loss on Wi-Fi are common and usually fixed by a better signal.
Common causes and fixes
- Weak or congested Wi-Fi: test again on a cable to rule it out.
- A faulty cable, port or modem: swap the cable and restart the modem.
- Congestion when the line is full: run "Test under load" and enable SQM if loss appears only then.
- A problem at your provider or along the route: run the route trace and share the hops where loss starts.
Questions
How do I test for packet loss?
Press "Start packet loss test" to test your own connection. To test a specific host, enter it in the network echo form below and choose 10 attempts.
Why does a browser test show late replies instead of lost packets?
Browsers cannot send raw packets. They use TCP, which resends lost data, so loss appears as delay. Replies slower than two seconds are counted as lost.
Is 1% packet loss bad?
It is noticeable in calls and fast games. On a wired connection it should be 0%.
Can a website block ping?
Yes. Many hosts ignore ICMP echo requests, so 100% loss to one host does not always mean it is down. Use the port reachability test on port 443 instead.