There have been umpteen number of sites offering speed testing services for your internet connection, but some of them are bogus and most of them are inconsistent and unreliable. I bumped across a service which is free, reliable, consistent and almost accurate.
Check out Speed.io
From their web site: “speed.io measures your current internet speed to the nearest server (we have almost 50.000 server worldwide). We test your download (speed with which you receive data from internet), upload (speed with which you send data to the internet), connection test (maximal number of connections per minute) as well as ping (response time between your computer and the internet).”