Too Long; Didn't Read
Since Steam has no official sales data, the player counts for games that haven't become free will be used to estimate the most successful titles on the platform. Under this scope, the 10 best-selling Steam games are:
10. Counter-Strike
9. Monster Hunter World
8. Grand Theft Auto V
7. Among Us
6. Fallout 4
5. Terraria
4. Valheim
3. New World
2. Elden Ring
1. Cyberpunk 2077
Many of these games managed to keep their popularity, but others ended up unlucky over time. If Steam ever releases official sales numbers for their games, it will be interesting to see how well the most successful games hold up today.