Packet Loss Test
Run a browser-based check for lost requests and micro-disconnects. Because browsers cannot send raw network packets, we report what we can genuinely observe — requests that fail or time out — and explain exactly how that relates to packet loss.
Test duration
Short tests are useful for quick checks. Longer tests are better for finding intermittent problems.
Free, no signup. The advanced test also moves test data to measure latency under load: up to a few hundred MB on a fast connection, so switch it off on metered data.
Customize: goal, connection type
Connected via (optional — sharpens the diagnosis)
Request loss vs. packet loss
Packet loss is the share of network packets that never arrive. Tools like ping and traceroute measure it directly using ICMP, which browsers cannot send. Our test sends HTTPS requests every 500 ms and counts the ones that fail or exceed a 2-second timeout. We call this request loss.
TCP hides most real packet loss by retransmitting, so a single lost packet usually shows up as a delay rather than a failure. A failed request therefore means something more serious than one dropped packet — and small amounts of true packet loss (which hurt calls and games that use UDP) can be invisible to a browser test.
For that reason a clean result here is reassuring but not proof of zero packet loss, and a non-zero result is a real sign of trouble. True packet-loss measurement over WebRTC is on our roadmap and needs a server-side peer.
How much loss is a problem?
These are practical guidelines, not universal thresholds. Distance, network type and the app in use all change what is tolerable.
| Request loss | What it usually means |
|---|---|
| 0% | Nothing lost in this window |
| Occasional single failures | Worth watching; run a longer test |
| Repeated failures or gaps ≥ 1.5 s | A genuine interruption; check Wi-Fi vs. Ethernet, then the router and ISP |
What to do if you see loss
Repeat on Ethernet
Loss on Wi-Fi only points to the wireless link.
Restart the modem and router
Then retest to see if the pattern changes.
Save the evidence
Run a 5-minute test and use the ISP report to record timestamps, durations and counts.