How to test your internet speed on iPhone

Run the test

1. 1

   Get close to the router

   Testing from the far end of the flat measures your walls, not your line. Start next to the router, then repeat where you actually sit.

2. 2

   Stop other traffic

   A download, a backup or somebody streaming will show up as a slow line. Pause them.

3. 3

   Pick the connection you mean to measure

   Wi-Fi and cellular are different questions. Switch Wi-Fi off if it is the mobile connection you are checking.

4. 4

   Start the test

   One tap; the whole run is over in under 30 seconds.

5. 5

   Repeat it

   Two or three runs, and again in the evening. Results are saved to the history list, so the comparison is there when you need it.

What the three numbers mean

• Download — how fast data reaches you. This is the number that governs streaming, browsing and downloads, and the one providers advertise.
• Upload — how fast data leaves you. It matters for video calls, cloud backup and sending large files, and on many home connections it is far lower than download by design.
• Ping (latency) — how long a round trip takes, in milliseconds. Low ping is what makes a connection feel responsive; a fast line with high ping still feels sluggish in calls and games.

How much speed do you actually need?

Less than most people assume. Standard-definition video streaming needs only a few Mbps, HD is comfortable around 5–10 Mbps per stream, and 4K is the demanding case at roughly 25 Mbps per stream. Video calls need a few Mbps in both directions — which is why upload, not download, is usually what breaks a call.

The figures above are per simultaneous stream. A household running two 4K streams and a video call at once is asking for something quite different from one person browsing.

Why your result is lower than the speed you pay for

• Advertised speeds are the maximum the line can carry, measured at the router, in ideal conditions. Wi-Fi in a real home is not ideal conditions.
• Wi-Fi loses speed through distance, walls and interference from neighbouring networks. A wired device on the same line will usually be faster than any phone.
• Older iPhones and older routers cap out below the line's capability. If the hardware is the bottleneck, no plan upgrade will show up in a test.
• Evening congestion is real. The same connection can measure very differently at 09:00 and 21:00.
• Test servers vary. A distant server measures the route as well as the line.
• VPNs reduce measured speed, because traffic is taking a longer path. Turn one off before testing.

If the numbers look wrong

• Compare Wi-Fi against cellular. If cellular is dramatically faster, the problem is inside your home, not on your line.
• Test next to the router and then where the problem happens. A big gap points at coverage rather than the connection.
• Restart the router before concluding anything — it fixes more than it should.
• Collect several tests with timestamps before contacting your provider. A history carries weight that one screenshot does not.
• If speed is fine but everything still feels slow, look at ping and at which devices are on the network — that is a different diagnosis, and a network analyzer is the tool for it.