If you're looking to test that you're achieving speeds close to the headline speed of your plan then you need to ensure that your computer is plugged directly into your router. Testing over WiFi can impact on performance. More information about WiFi speeds can be found here.
Extra info for extra fast connections
If you're on a really fast connection (200Mbps, 500Mbps or MAX/1Gbps) then you also need to:
Be using a router supplied by Vorco, or ensure that the router you have is capable of the throughput you've signed up for.
Have a computer with an Intel i5 6th Generation CPU or better and a Gigabit Ethernet NIC (network card).
Use Speedtest.net from the Windows Store Speedtest app, or Google Chrome version 55 or above. Other browsers have been unable to keep up with really high speeds in our own testing.
Test to the Vorco Speedtest.net server. This particularly applies to 500Mbps and MAX/1Gbps plans where the path between Vorco and the other Speedtest.net server crosses the open Internet and therefore is out of our control.
Be the only device connected to your router while testing. Other devices on your network subtract from your total available bandwidth.
As long as you meet the above requirements then we expect you'll see results that are pretty close to the maximum speed of your plan, most of the time.