Read your internet speed test results: Mbps, ping and jitter
Understand download, upload, ping, jitter and ping under load, convert Mbps to MB/s, and run a fairer test before you contact your provider.
Mbps is not MB/s
Speed tests report megabits per second (Mbps). File sizes and download progress bars usually use megabytes (MB). One byte is eight bits, so divide by 8: a 200 Mbps connection can move at most about 25 MB per second. Real downloads come in lower because of protocol overhead, the speed of the server you download from and what else is using the connection.
What each number tells you
- Download
- How fast data arrives. It matters for streaming, updates and downloading files.
- Upload
- How fast you can send data. It matters for video calls, cloud backups and sending large files, and is often much lower than download.
- Ping
- The round-trip time of a small request, in milliseconds. Lower is better for games and calls.
- Jitter
- How much the ping varies from one request to the next. A steady 30 ms feels better than a ping that swings between 10 and 90 ms.
- Ping under load
- The ping measured while the download test is running. A large increase compared with idle ping can be consistent with queueing under load, often discussed as bufferbloat. The result alone does not locate the source of the delay.
Internet Speed Test measures ping and jitter first with small requests, then downloads and uploads data over several parallel connections for a few seconds each. It ignores the first moments as warm-up and measures ping under load during the download.
Worked example: reading one result
These numbers are invented to show the reasoning, not measured on a real connection.
| Measurement | Value | Reading |
|---|---|---|
| Download | 480 Mbps | More than enough for several HD or 4K streams and large downloads. |
| Upload | 22 Mbps | Fine for video calls, but a large cloud backup will take a while. |
| Ping | 14 ms | Good when the connection is idle. |
| Jitter | 3 ms | Very steady. |
| Ping under load | 190 ms | Latency rises sharply while data is moving, so calls and games can stutter whenever someone downloads. |
The speed is high, yet the connection still feels bad during a busy moment. The gap between 14 ms and 190 ms shows increased latency during this test. It does not identify whether the delay originates in the local router, another device, an upstream link or the route to the test service. Router settings that manage queues, sometimes called smart queue management or QoS, may help. A higher advertised speed is not, by itself, a diagnosis or a guaranteed fix; compare repeatable wired tests before deciding what to change.
How to run a fairer test
- Use an Ethernet cable if you can. Wi-Fi speed depends on distance, walls, interference and the band you are connected to.
- Pause other downloads, streams and backups on every device in the home.
- Run the test three times, at different times of day, and compare. One result is an estimate and results vary from test to test.
- Test with and without a VPN if you use one. A VPN can lower the result, so compare using the setup you normally use.
- If Wi-Fi is much slower than Ethernet, the problem is the Wi-Fi link, not the plan you pay for.
The page lists rough speeds for common activities. Treat them as starting points, because streaming quality, the service and how many people share the connection all change what you need.
Data use and privacy
A speed test moves real data. On a fast connection it can use hundreds of megabytes or more, so avoid it on a metered or mobile plan. The test runs against Cloudflare’s network, so Cloudflare receives your IP address and the test traffic. The optional ISP lookup runs only if you click it and sends your IP address to ipwho.is. Nothing else about the test is sent to this website.
When to contact your provider
A browser test against one server is a good indicator but not a laboratory measurement. Consider contacting your provider if results on Ethernet stay well below the speed in your plan across several tests at different times of day, or if ping under load is high on a wired connection. Bring the numbers, the times and a note that you tested on Ethernet.