The test runs three short measurements against a nearby test endpoint served from a Cloudflare worker: ping (how many milliseconds a tiny request takes to come back, which decides how responsive calls and games feel), download speed (how fast data arrives, in Mbps — this is what video streaming and file downloads depend on), and upload speed (how fast data leaves your device, which matters for video calls, backups and sending large files).
Results describe the connection between your device and the test endpoint at that moment — not a guaranteed line speed. Wi-Fi quality, distance to the router, other devices on the network and your provider's congestion all move the numbers, so run the test twice and compare, ideally once close to the router and once where you actually work.
Close heavy downloads, streams and cloud backups on this device for a cleaner measurement.
Press the start button and let the ping, download and upload phases run one after another.
Read the three results: ping in milliseconds, download and upload in Mbps.
Re-run the test at a different spot or time of day if the first result surprises you.
Checking whether a new broadband plan delivers roughly the speeds it advertises.
Diagnosing a laggy video call: high ping or low upload is usually the culprit.
Comparing Wi-Fi coverage between rooms before deciding where to put a desk or a mesh node.
Your browser exchanges test data with a measurement endpoint on a Cloudflare worker: small requests for ping, a larger download to time throughput, and an upload of generated data. The amount of data is modest and the results are calculated locally in the page.
Because the network changes between runs. Wi-Fi interference, other people streaming, provider congestion and even the test endpoint's load all shift the numbers. Trends across several runs mean more than any single measurement.
Ping under about 30 ms feels responsive for calls and games; 100 ms or more is noticeable. Download needs are household-dependent — roughly 25 Mbps handles one 4K stream — while upload of 10 Mbps or more keeps video calls and backups comfortable.
Each run transfers a limited amount of test data to measure throughput — think in the range of a few photos, not a video. On a capped mobile plan, prefer running it on Wi-Fi.