Speedtest.net is a web service that provides free analysis of Internet access performance metrics, such as connection data rate and latency. It was founded by Ookla in 2006, and is based in Seattle, Washington. The service measures the bandwidth (speed) and latency of a visitor's Internet connection against one of 4,759 geographically dispersed servers (as of August 2016) located around the world. Each test measures the data rate for the download direction, i.e. from the server to the user computer, and the upload data rate, i.e. from the user's computer to the server. The tests are performed within the user's web browser or within apps. As of September 2018, over 21 billion speed tests have been completed.Tests were previously performed using the HTTP protocol at Layer 7 of the OSI model. To further improve accuracy, Speedtest.net now performs tests via direct TCP sockets and uses a custom protocol for communication between servers and clients. The site also offers detailed statistics based on test results. This data has been used by numerous publications in the analysis of Internet access data rates around the world.