Internet Speed Test
Updated · Free · No sign-up · Starts only when you press the button
Test your Wi-Fi or mobile connection: download and upload speed, ping (latency), jitter and how much latency rises while the connection is busy. The result comes with a short, plain-English guide to what it means for video, video calls and gaming.
Nothing starts until you press the button. Phones get a light test (up to about 30 MB) by default; the standard test uses up to about 76 MB.
This test uses up to about 30 MB of data. On a mobile plan it counts toward your data allowance, so switch to Wi-Fi if your data is limited.
While testing, your IP address and other connection details are sent to the test server (Cloudflare). Your results are not sent to Cloudflare.
Rough speed guide used in the verdict
| Activity | What the verdict looks for |
|---|---|
| HD (1080p) video | Download 5 Mbps or more |
| 4K video | Download 25 Mbps or more |
| HD video calls | Download and upload 3 Mbps or more, ping under 150 ms |
| Online gaming | Ping 50 ms or less, jitter 20 ms or less |
| Busy connection | Latency rising more than 100 ms under load is flagged |
How the test works
- The test engine is Cloudflare Speed Test (open source, MIT). It exchanges data with the nearest Cloudflare server.
- Download and upload speeds are the 90th percentile of several transfers. Ping is the median of 20 requests; jitter is the average change between consecutive pings.
- Each step stops growing once a single request takes longer than one second, so slower connections use less data than the maximum shown.
- Packet loss is not measured.
Getting a reliable result
- Close downloads, streaming and other busy tabs before testing.
- On Wi-Fi, test near the router first, then where you usually sit.
- Run the test two or three times and look at the typical value rather than a single best or worst run.
- Speeds vary with time of day, signal strength and the device itself, so treat any single result as a snapshot.
Sources
- Cloudflare Speed Test on GitHub — test engine, MIT license
- NIA official speed test (South Korea) — government-certified measurement for Korean internet and mobile service quality
- YouTube Help — recommended speeds by video quality
- Netflix Help — recommended speeds by video quality
Checked 2026-10-29.
Frequently asked questions
How much data does the speed test use?
The light test uses up to about 30 MB and the standard test up to about 76 MB. Slower connections use less because the test stops stepping up once a request takes over a second. The page shows an estimate of the test transfer when it finishes.
What is the difference between Mbps and MB/s?
Mbps is megabits per second; MB/s is megabytes per second. One byte is eight bits, so 100 Mbps is roughly 12.5 MB/s in theory. Internet plans and speed tests almost always use Mbps.
What are ping and jitter?
Ping (latency) is the round-trip time to the server in milliseconds; lower feels more responsive. Jitter is how much ping varies from one request to the next; high jitter can make calls and games stutter.
What does latency under load mean?
It is the ping measured while the connection is busy downloading or uploading. If it rises a lot compared with idle ping, calls and games may lag whenever someone on the same connection is downloading or streaming.
Why is my result different every time?
Wi-Fi signal, other devices on the network, congestion at the time, the device itself and other browser tabs all change the result. Run a few tests and use the typical value.
What information is sent during the test?
The test exchanges data with Cloudflare, so your IP address and other connection details reach Cloudflare as with any website. Results are not reported to Cloudflare, and this site does not store your results.