I find it weird that the hours played count is usually so off. For example, it says I've played 38 hours of Dead Island while the actual games says I've played around 30. I just find it weird because I didn't leave the game running whatsoever. Have you guys experienced this? Seems strange to me.

It's counting in seasons of love.

@NekuSakuraba:

Steam counts everything, anytime the game is running.

The reason it does not coincide with game hours is because games usually only count ingame time. Frequently excluding menus, cut scenes, dialogue, etc. Also games almost always count it as one continuous playthough and exclude stuff that you played but did not load from. Say you play half an hour then reload to a previous save because of a bug/crash whatever, game is not going to count that time, Steam will.

As a result Steam time_played will almost always display more then what the games tell you themselves on saves.

It says I've played 57 hours of Costume Quest when it's actually like 3 hours, I find that really weird
 
Maybe I left the game running in the background?

It says Ive played 138 hours of Dota 2 but I still suck at it, it is definitively wrong.

@Tennmuerti said:

@NekuSakuraba:

Steam counts everything, anytime the game is running.

The reason it does not coincide with game hours is because games usually only count ingame time. Frequently excluding menus, cut scenes, dialogue, etc. Also games almost always count it as one continuous playthough and exclude stuff that you played but did not load from. Say you play half an hour then reload to a previous save because of a bug/crash whatever, game is not going to count that time, Steam will.

As a result Steam time_played will almost always display more then what the games tell you themselves on saves.

This is your answer; Steam just monitors if the game's .exe is running or not.

Steam's hour counter is barely a decent estimate, the in-game one is better but still not as good.

I had a torrid love affair with the original Witcher for a couple of months, for some reason I would just leave it running when I went to work and seamlessly pick it up when I returned home. Now it's my most played game with over six hundred hours. Hilarious.