How Online Slot Machines Work

When you play a slot machine at a land-based casino, you pull on a lever, and a series of mechanical events result in your win or loss—or so it would seem.  When you play a slot machine online, though, you obviously are not pulling on a lever.  The reels that turn on your screen are not really reels, and there are no mechanical parts to speak of.  This may make you wonder: How is your win or loss determined?  What makes the reels “turn” and certain symbols appear?  How do online slot machines work on online casino sites?

Actually, as it turns out, these days  land-based and online casinos work the exact same way.  Those mechanical days are actually long gone, and what remains is a mere illusion.  Today, both physical machines and virtual machines work using something called a random number generator, or RNG. 

What is a random number generator?  It’s software.  It’s a computer program that does exactly what it sounds like it’s designed to do.  It picks random numbers.  First, it randomly selects a winning sequence of symbols using an algorithm.  Then it randomly selects a set of reels to display on your screen (or offline, on the machine itself).  Each time it does this, the RNG generates around four billion numbers.  That is on every single spin.  Since there are so many combinations, it is extremely unlikely you will win. 

One thing that is important to know is that the RNG does not remember past spins—just as a roulette wheel does not.  The Gambler’s Fallacy is the mistaken belief that random games do have memories of previous events, and that the more times you lose, the closer you are to winning.  This is not actually true, though.  Since the RNG has no memory, your odds of winning are the exact same for every spin.  The reels on the screen exist to reinforce the illusion that there is some mechanical process at work, and that you can somehow beat the odds.

Your next question is probably this:  Is it possible to hack an online slot machine at a casino website and cheat your way to riches?  It might seem like you could, and plenty of people have given it a shot.  RNGs are very good at what they do, however, and undergo rigorous quality control testing.  They truly are random, so there is no way you can guess the algorithm which is used, and which itself is pretty random.  So there is no way to calculate the odds or manipulate the RNG in any way. 

Nonetheless, that’s not really the point of playing an online slot machine.  If you’re reading this and are curious about how online slots work, it’s probably because you love the game, along with all the chance that it entails.  Suffice to say, RNGs are quite mysterious and are very interesting from a mathematical perspective, but you don’t need to understand their workings in-depth to enjoy playing online slot machines.  And even though it’s unlikely you’ll win a huge jackpot, who knows—every winner has felt that way before it happened!