Fast.com is a simple internet connection speed test tool launched by Netflix. It starts automatically upon visiting the page, gives you the real-time download speeds, and gives you additional information about your connection with the click of a button. You can also compare your results with the famous Ookla’s Speedtest.net.
Netflix measures your current download speed by performing a series of downloads from Netflix servers. Click the "Show More Info" button to upload speed, latency, and testing location, and optionally change the settings used to make these tests.