Portal 2

Released Apr 17, 2011Valve

PlayStationPCXbox

The "Perpetual Testing Initiative" has been expanded to allow you to design co-op puzzles for you and your friends!

Estimated sales today

Low confidence

14.6M – 24.3M

units · live estimate

How we estimate

Our estimate combines several independent calculation methods that we continuously cross-check to get as close to the real figure as possible.

The confidence score reflects how consistent these methods are: when they agree, the range tightens; when they diverge, we flag it clearly.