Packet Loss Test

1% loss is enough to break voice calls. Most speed tests don't show it.

Packet loss is the percentage of packets sent that never arrive at the other end. Unlike ping or speed, packet loss is binary for many apps — a lost packet means a dropped video frame, a gap in audio, a stutter in a game. A connection can be fast and low-ping but have 2% loss, which makes it functionally useless for calls.

Most consumer speed tests skip packet loss entirely or measure it badly. Signalyzr sends enough probes to detect loss down to 0.5% and tells you whether the loss is local (Wi-Fi, router) or upstream (ISP).

What this measures

  • Probe count — we send enough to detect 0.5% loss reliably
  • Burst vs uniform — is the loss patterned or random?
  • Round-trip loss vs one-way loss (where possible to distinguish)

How it works

  1. Send a burst of small probes to the nearest server
  2. Count how many round-trip with a valid response
  3. Compute loss percentage and burst-vs-uniform pattern
  4. Match the pattern to a likely cause (Wi-Fi, ISP, mobile signal, etc.)

Why this matters

Packet loss is invisible to most users until they have a call that breaks. By then they've already had a bad experience. Detecting it early — and fixing it — is the difference between a connection that 'works' on paper and one that actually works for video calls and games.

Top fixes

  • If loss is on Wi-Fi only: change Wi-Fi channel or switch to 5 GHz
  • If loss is bursty (clumps): suspect Wi-Fi interference from microwave / neighbour AP
  • If loss is uniform: suspect ISP-side congestion — try at 6 AM to confirm peak issue
  • If loss appears on wired ethernet: replace the cable, then call ISP
  • On mobile: loss with weak signal — move to better coverage

FAQs

What is acceptable packet loss?

Zero is ideal. Anything under 0.5% is generally acceptable for browsing and streaming. Above 1% you'll notice voice call quality drop. Above 2% the connection is functionally broken for real-time apps.

What causes packet loss?

Wi-Fi interference, weak signal, faulty cable, congested ISP backhaul, bad routing upstream, or hardware problems in your modem/router. Each has a different fix — we identify which.

How can I tell if packet loss is my Wi-Fi or my ISP?

Run the packet loss test on Wi-Fi, then run it again on wired ethernet (or via mobile hotspot). If loss disappears on wired/hotspot, it's Wi-Fi. If it persists, it's your ISP or modem.

Can packet loss be fixed?

Yes, in most cases. Wi-Fi loss fixes by channel change or moving the router. Modem loss fixes by replacing the modem. ISP loss requires a complaint with the loss percentages we give you (ISPs ignore vague 'slow' complaints but act on specific loss data).

Run free packet loss test →

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Signalyzr is a free, privacy-first network diagnostic tool made in India. Loading the diagnostic app…