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How to Properly Test Your Broadband Speed

Are you getting what you paid for? How to test accurately.

The Wi-Fi Trap

The number one complaint ISPs receive is: “I pay for 900Mbps but I only get 300Mbps on my phone.” In 99% of cases, the line is fine. The bottleneck is the Wi-Fi.

Wi-Fi is a radio signal. It degrades through walls. It is shared with neighbours. And most importantly, mobile chips are limited. An older phone simply cannot download at 900Mbps over Wi-Fi, no matter how fast your router is.

How to Run a “Valid” Speed Test

To verify that CityFibre and your ISP are delivering the speed you paid for, you must rule out Wi-Fi.

  1. Get a Cable: Use a Cat5e or Cat6 Ethernet cable.
  2. Plug In: Connect a laptop or PC directly into the LAN port of your router.
  3. Close Apps: Shut down Steam, Netflix, Windows Updates, and any other bandwidth hogs.
  4. Use the App: Don’t use a browser. Browsers can struggle to render 1Gbps test data. Download the Speedtest.net desktop app.

The Magic Number: 940Mbps

If you are on a “1 Gigabit” connection, a perfect speed test result is usually around 940Mbps. Why not 1000?

This is due to TCP/IP Overhead. About 6% of the data is used for the digital “envelopes” (headers) that carry your data packets. The payload (your file) gets the remaining 940Mbps. If you see ~900Mbps+, your line is perfect.

Testing on Wi-Fi

If you must test on Wi-Fi:

  • Stand 2 meters from the router.

  • Use a modern device (Wi-Fi 6 compatible).

  • Ensure you are on the 5GHz band.

Expect 400-600Mbps on Wi-Fi 5, and 600-800Mbps on Wi-Fi 6. Getting the full Gig over air is very difficult without expensive Wi-Fi 6E/7 gear.