caniuse.com

http://caniuse.com/ is a very handy web site for web developers. It shows browser support for every HTML/CSS/JavaScript feature. Information is very detailed and shows current support level and estimated support level in future version of browsers. Partial supports are also shown with color codes.

Screen Shot 2013 07 07 at 2 11 58 PM

caniuse.com, 6.0 out of 10 based on 1 rating