SpeedTestLab

SpeedTestLab network tool

Packet Loss Test

True ICMP packet loss is not available in a normal browser. This page can report HTTP probe failures instead, and explains the limit.

A browser cannot run a true ICMP packet-loss test to an arbitrary host. This page reports HTTP probe timeouts as a related diagnostic, not IP-layer loss.

051025501002505001000

Ready

Tests send generated traffic to Cloudflare’s speed-test network and use your data allowance. Cloudflare processes your IP address and technical request data under its privacy policy. This site disables the SDK’s separate results logging. Results describe this device-to-Cloudflare path, not a guaranteed ISP speed. Privacy Policy

Ping—ms
Jitter—ms
How this test measures your connection

Node: local-dev

Ping here is HTTP round-trip time after one warmup sample, not ICMP. Speeds use decimal Mbps from bytes and elapsed time.

What does this tool measure?

A normal web page cannot send arbitrary ICMP echo packets. This tool therefore reports failed HTTP probes as an application-path diagnostic and never labels them as IP-layer packet loss.

How do I use it?

  1. Start the probe series.
  2. Keep the tab active while all requests run.
  3. Review failed probes together with HTTP latency and jitter.
  4. Use an operating-system or router diagnostic when true ICMP or interface statistics are required.

How should I read the result?

A failed HTTP probe means the request did not complete successfully within this browser test. It can be caused by connectivity, timeout, server, browser, or rate-limit conditions.

What are the technical limits?

HTTP probe failures are not interchangeable with network-layer packet-loss percentage. SpeedTestLab does not fabricate ICMP results.

Frequently asked questions

Can a browser measure true packet loss?

Not to an arbitrary host with ICMP. Specialized WebRTC tests can measure loss within their own media session, but that is a different scope.

What should I use for true packet loss?

Use trusted operating-system tools, router diagnostics, or a test designed for a specific real-time session.

More Network Tools

Diagnose this connection, then read what the numbers mean.

WiFi Speed TestThroughput on the current Wi‑Fi connection, not radio diagnostics.Download Speed TestFocuses on download throughput only.Upload Speed TestUpload-only test with generated data.Ping TestHTTP latency, not system ICMP ping.Jitter TestLatency variation for calls and games.Packet Loss TestHonest HTTP probe diagnostic, not ICMP loss.Internet Stability TestLatency trend over a short window.Network Quality TestWeighted reference score, not a repair verdict.Speed Unit ConverterMbps, MB/s, and related units.Download Time CalculatorEstimate time from size and speed.Speed Test HistoryLocal-only test log.