Top games by current player count
Current Players Peak Today   Game
 
768,201 1,013,674   Dota 2
582,359 594,701   Counter-Strike: Global Offensive
82,804 99,424   XCOM 2
64,734 73,404   Football Manager 2016
58,782 60,554   Team Fortress 2
51,787 56,595   Sid Meier's Civilization V
51,758 53,214   ARK: Survival Evolved
50,836 52,864   Rust
45,919 53,561   Grand Theft Auto V
43,335 45,686   Garry's Mod

Steam Hardware & Software Survey
Steam Stats