See How Fast Is Your Connection
Speedtest.net is a free broadband connection analysis website founded by Ookla Net Metrics in 2006. Users can test their internet speed against hundreds of geographically dispersed servers around the world.
At the end of each test, users are presented with their download (the speed of data from the server to your computer) and upload (the speed of sending data from your computer to the server) bandwidth speeds.
The tests are performed completely within your web browser over HTTP (just like normal web browsing). Since its inception, well over 1 billion speed tests have been conducted on Speedtest.net.
Wikipedia
At the end of each test, users are presented with their download (the speed of data from the server to your computer) and upload (the speed of sending data from your computer to the server) bandwidth speeds.
The tests are performed completely within your web browser over HTTP (just like normal web browsing). Since its inception, well over 1 billion speed tests have been conducted on Speedtest.net.
Wikipedia