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How to Test Your Internet Speed (Download, Upload, Ping)

4 min readUpdated 5 October 2026

To test your internet speed, open Speed Test and press Start test. In under a minute you get your Download and Upload speed in Mbps, your Latency (ping) and Jitter in milliseconds, and a plain-language verdict on what the connection is good for, from HD video to online gaming.

It is free, needs no account or app and works in any browser on a phone, tablet or computer. The test exchanges only random test data with Cloudflare's speed test servers; no files or personal data are sent, and your results are kept only on your own device.

Do it now with Speed TestFree, no sign-up, works on any device.

Step by step

  1. 1Get a fair starting pointPause downloads, streaming and video calls on your network, and close other heavy tabs. Anything else using the connection lowers the result.
  2. 2Choose full test or Data saverOn Wi-Fi or a home line, leave Data saver off: the full test uses up to about 450 MB on a fast connection. On mobile data, turn it on for a shorter test that uses at most about 20 MB. It switches on by itself when your browser reports mobile data.
  3. 3Press Start testThe status above the gauge moves through Measuring latency…, Testing download… and Testing upload…. The whole run takes well under a minute; press Stop at any time to cancel.
  4. 4Read your four numbersDownload and Upload are in Mbps, Latency and Jitter in ms. Under latency you also see the ping “under load”, measured while the download was running.
  5. 5See what it means and save itWhat this means rates web, HD video, 4K streaming, video calls, gaming, big downloads and uploads as Great, OK or Struggles. Copy results gives you a text summary to send to your provider, and History on this device keeps your last 20 tests.

What the test actually measures

The test talks to Cloudflare's speed test servers (speed.cloudflare.com), normally at the data centre closest to you; its short location code appears as Cloudflare server · … above the gauge. So it measures the path from your device to that nearby server, not to one particular website or game.

Latency is the median of about 20 tiny requests (the first one, which sets up the connection, is thrown away). Jitter is how much those times change from one request to the next. Download and Upload then run several parallel connections for up to 8 seconds each, and the result reflects the speed your line sustains once it has warmed up, rather than the slow first moments.

Tip: A big gap between idle latency and latency “under load” means your connection gets laggy when it is busy. That is why a call can stutter while someone else is downloading.

What speed do you need?

These are the thresholds the tool uses for Great:

  • HD video: 8 Mbps download (OK from 4 Mbps).
  • 4K streaming: 25 Mbps download (OK from 15 Mbps).
  • Video calls: 4 Mbps down and 3 Mbps up, latency under 100 ms and jitter under 30 ms.
  • Online gaming: latency under 40 ms and jitter under 10 ms — speed matters less than a steady, low ping.
  • Big downloads: 100 Mbps; uploading & backups: 20 Mbps upload.

Tip: Several people or devices at once add up: two 4K streams need roughly twice the speed of one.

Why your result differs from your plan

Internet plans are sold as “up to” a speed, and that is measured at the line, not on your phone. Wi-Fi distance and walls, an older device or router, a VPN and other traffic on your network all lower what a browser test sees. For the clearest picture, run the test on a computer plugged into the router with a cable, then again on Wi-Fi in the room you use.

Speeds here are in megabits per second. Download managers usually show megabytes per second, which is 8 times smaller: 100 Mbps is about 12.5 MB/s. Testing at different times of day also helps, because evening congestion is common.

If the test won't run or looks wrong

The common messages and what to do:

  • “Couldn't reach the speed test servers” — a firewall, VPN or content blocker may be blocking speed.cloudflare.com. Allow it or pause the blocker, then try again.
  • “You're offline” — your device has no connection at all. Reconnect to Wi-Fi or mobile data first.
  • “Upload test didn't finish” — the download result is kept; run the test again to get upload.
  • “Very fast connection — data saver may under-read it” — on lines over 100 Mbps, turn Data saver off for an accurate figure.

Tip: Before a video interview, also check your camera and microphone with Cam & Mic Check, and see your browser and hardware details in Device Report.

Questions people ask

How much data does a speed test use?
The full test uses up to about 450 MB on a very fast connection, less on slower ones because it stops after a few seconds. With Data saver on, it uses at most about 20 MB, which is sensible on a mobile plan.
What is a good ping?
Under 40 ms is great for online gaming, and under 100 ms is fine for video calls. Steady matters too: jitter under 10 ms for games and under 30 ms for calls.
Is this speed test private?
Only random test data is sent and received. Like any website, Cloudflare sees your IP address, but no files or personal data are involved, and your history is stored only in your browser. You can delete it with Clear history.
Why is my phone slower than my laptop?
Usually Wi-Fi: phones often sit further from the router or support older Wi-Fi standards. Test both in the same spot to compare fairly.
Do it now with Speed TestFree, no sign-up, works on any device.

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