A speed test gives you four numbers. Each describes a different aspect of your connection, and which one matters most depends on what you do online.
Download speed
Download speed is how much data per second can reach your device, measured in megabits per second (Mbps). It affects how quickly web pages load, how high a video quality you can stream, and how long large downloads take. Remember there are 8 bits in a byte: a 100 Mbps connection downloads at most about 12.5 megabytes per second.
Upload speed
Upload speed is how fast you can send data out – on video calls, when sharing files, backing up photos to the cloud or live-streaming. Cable and DSL plans often have upload speeds 10–20 times lower than download; fibre plans are frequently symmetrical.
Ping (latency)
Ping is the round-trip time for a small message to reach a server and come back, in milliseconds (ms). It is what makes a connection feel responsive. A 1,000 Mbps connection with 150 ms ping will still feel laggy in a game, while 20 Mbps with 15 ms feels snappy for browsing and calls. Latency depends heavily on physical distance to the server.
Jitter
Jitter is how much the ping changes between consecutive measurements. Real-time applications like voice calls send small packets at a steady rhythm; if they arrive unevenly, the app has to buffer or drop audio. Under 10 ms of jitter is good for calls and gaming.
How much speed do I need?
| Activity (per device) | Download | Upload | Latency |
|---|---|---|---|
| Web browsing, email | 1–5 Mbps | <1 Mbps | <100 ms |
| HD video streaming | 5–8 Mbps | – | any |
| 4K video streaming | 15–25 Mbps | – | any |
| HD video call | 2–4 Mbps | 2–4 Mbps | <100 ms, low jitter |
| Online gaming | 3–10 Mbps | 1–3 Mbps | <50 ms ideally |
| Uploading large files | – | 10+ Mbps | any |
These are approximate rule-of-thumb figures. Add up the needs of everyone who uses the internet at the same time, then allow some headroom.
Getting an accurate measurement
- Test on a device connected by Ethernet cable, or close to the router on 5 GHz Wi-Fi.
- Pause other downloads, streaming and cloud backups.
- Run several tests at different times and look at the typical result.
- Remember that a test only measures the route to that test's server.
Ready? Run the IPandNet speed test.