
Measured by number of units sold.
Including pack-in games included with consoles.
However Free games and Tetris that has titles across 30 years do NOT count.
Lately I’ve been getting more into classic table games, especially blackjack. It’s a nice break from all the flashy stuff and really keeps your mind engaged. If you're into that kind of thing too, I found a solid page at https://slotier.org/table-games/blackjack/ that’s packed with useful info. They cover different blackjack variations and even offer some strategy pointers. I didn’t realize how much depth the game had until I started reading more. Definitely worth a look if you enjoy skill-based games.
GTA 5 took 10 years to dethrone Minecraft & become the highest selling game.
If GTA 6 does become the highest selling it won’t do it in 1 year as the market creator ( @CamLawlett) has mentioned

@Kiniaczu Nope by the 01/Jan/2027 more copies than any other single video game. so at least a year of runway depending on when it releases in 2025