The number of slots on any given casino grows at a steady pace as you games are released. The casinos that have the most developers signed up will grow the fastest.
The biggest online slot selection is currently in VideoSlots casino. They have taken it as their mission to bring as many games as possible onto one platform.
VideoSlots celebrated their 8,000th game release in August of 2022. Unfortunately, not all games are available on every locale, and Canadian players at that time had to settle for roughly 6,000 games.
Normally a casino can be considered to have a lot of games if there are at least 2,000 titles, like on Pixel Bet Casino.