While it's not possible to carry out conclusive performance testing on VPN services due to the wide range of factors that can affect the speeds users see, we carry out speed tests to get a feel for how each service performs. We test all services using their clients' default settings unless changes are required for connection stability.
We run tests from a London-based connection that typically sees un-VPN'd speeds of over 500Mbit/s. We test multiple servers from each provider in three locations: the UK, the Netherlands and the USA, and retest any anomalous results.
Our core tests are large file downloads via HTTP, pulled down via curl on a standard Windows 10 PC for accurate throughput recording. Note that these figures can only ever be a snapshot of performance at a single point in time, rather than being fully representative. We refer back to prior test results where relevant.
While UK and Dutch endpoints can, from the best VPN services, come close to matching the speed a fast internet connection without a VPN, connection speeds to the USA are typically far slower, with many VPNs producing download speeds of less than 100Mbit on even the fastest of internet connections.
We also test whether we're able to view region-locked streaming video content from various streaming services, which have included Netflix, Crunchyroll and Shudder in the US, and All 4, Channel 5 and BBC iPlayer in the UK. Our current core video tests are Netflix and Disney+ in the US, plus BBC iPlayer, all of which work hard to identify and block IP addresses associated with VPN endpoints, so what works one month may not the next.