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Internet Speed Test

Measure your download and upload speed, latency and jitter in the browser against Cloudflare's global network.

Ready when you are

—Download
—Upload
—Latency
—Jitter

Measurement log

StepSizeTimeSpeed

Latency is the median of ten 0-byte requests; download streams 1 MB, 10 MB and then 25 MB from the nearest Cloudflare edge and reports the fastest sustained stretch; upload posts random bytes back. Results depend on your Wi-Fi, the browser and how busy the network is.

How to run the speed test

  1. Close other downloads, video calls and streaming tabs — they share the same connection and will drag the result down.
  2. Press Start test and leave the tab in the foreground; the gauge shows live speed while latency, download and upload are measured in turn.
  3. Read the four numbers: download and upload in Mbps, latency and jitter in milliseconds. Run it two or three times and take the best result.

FAQ

Why is the result lower than the speed I pay for?

A browser test measures what one HTTPS stream can pull through your Wi-Fi, your device and the whole path to the edge server. Wi-Fi, an old router, a busy household or a throttled CPU can each cut the number well below the line rate. A cabled connection on a quiet network is the fairest comparison.

What do latency and jitter mean?

Latency is how long a round trip takes — it decides how responsive games, video calls and web browsing feel. Jitter is how much that round trip varies; high jitter causes stuttering audio and video even when bandwidth looks fine.

How much data does the test use?

Up to roughly 40 MB for a fast connection (25 MB down, 10 MB up), and much less on a slow one because the test stops early. Avoid running it repeatedly on a metered mobile plan.