Microsoft Research has released their Network Speed Test app for Windows 8/RT devices in Windows Store. They have already released the same app in Windows Phone Store last month.
How fast is your Internet connection?
Network Speed Test measures your network delay, download speed and upload speed.
Using servers all over the world, Network Speed Test measures your network connection’s latency and throughput. Based on your connection’s speed, Network Speed Test will tell you what activities you might be able to do, such as stream music or video calls. Slide to the right to see a history of your previous tests for easy comparisons.
When you test your network using the Network Speed Test, certain characteristics of your device and the network connection will be sent to Microsoft to help improve our understanding of network quality and availability. If you consent, we may also collect information about your location at the time of the test. The data we collect is not associated with you, and will not be used to identify or contact you or for other purposes like targeted marketing. For additional information, see our privacy statement.
Measure your network latency, download and upload speeds.
Understand what activities, such as streaming music, you might be able to do.
See information about your network, such as the SSID and BSSID when you are connected to a Wi-Fi hotspot.
See your past network performance history.
Download it here from Windows Store for free.