My go-to website for testing internet speed was speedtest.net in school as well as college days. In 2016, Netflix launched its own website fast.com and I instantly switched. It was and is simplicity at its best. You open the website and that’s all. No need to click any button. The test starts automatically. No ads. Clean design. No jargon. It’s reliable. It’s fast! It does one thing and does that well.
Recently, I checked the traffic data on Similarweb. In July 2022, the incumbent speedtest.net had 94.7M visits while fast.com had an impressive 61M visits. This is crazy, right? In some countries like India and Japan, fast.com is already getting more traffic than speedtest.net. It feels good to see a product get such fast adoption (for reference, speedtest.net was launched in 2006!).
But what’s in it for Netflix? Well, some Internet Service Providers (ISPs) were found to throttle Netflix. ISPs also have an incentive to prioritize the servers of speed testing websites to make them look good. In a genius move, Netflix launched fast.com, using Netflix’s servers to calculate the internet speed. If an ISP selectively throttles Netflix, the end user will know by simply going to fast.com.
Remember Volkswagen emissions scandal? Goodhart’s law is everywhere. fast.com is Netflix’s way to keep ISPs in check. Kudos to the team that came up with the idea and executed it so brilliantly.