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Random Number Generators

Random Number Generator

If you’ve been playing casino games online for a while, you’ll probably have at least heard of random number generators. These hidden pieces of software control the outcomes of most online casino games, including video slots, card games like baccarat and blackjack, and every spin of the roulette wheel.

Yet the concept can seem unfamiliar even to the most tech-savvy player. What are they, and how do they work? In this piece, we’re going to give you the lowdown.

This is everything you need to know about random number generators.

Random Number Generators Explained

If you’ve ever wondered what force decides whether you get a 10 and an ace or a pair of threes while playing digital blackjack, you’ve stumbled upon it here. It’s an RNG.

These slick pieces of software control the outcomes of casino games by generating a series of random numbers associated with symbols such as slots icons, numbers on a roulette wheel, or digital cards.

How are they defined as random? It’s simple – if they can’t reasonably be predicted, they are considered random. That’s good enough for most people.

To be absolutely sure you’re playing games which have trustworthy algorithms powered by fair RNGs, we recommend sticking to games from respected casino software houses. You can learn more about these by clicking the button below.

How Random Number Generators Work

To truly understand the complexities of how RNGs work, you would need to understand advanced computer programing. Luckily, we don’t need to understand them on that level. We just need to know enough to grasp the important concepts needed to gain an understanding of how they function in theory.

Online casinos use a specific type of RNG called a Pseudo Random Number Generator. These are unique in that they don’t require any input. All they need is one number (called a seed number) and a computer algorithm to determine outcomes.

Some RNGs can produce billion of numbers per second, meaning the results are truly unpredictable by any reasonable means. The day may come when some sort of advanced artificial intelligence can predict them, but that’s still a long way off!

That said, the sharpest among you might have already realized that RNGs are not truly random in the purest sense of the word. While the numbers they spit out are virtually unpredictable, they are nonetheless determined by seed number and the computer algorithm.

What’s more – the algorithm only has so many options before it has to double back and repeat. This has led some people to believe that playing casino games for long enough and recording the outcomes will uncover the algorithm.

Others think that would take far too much time and prefer the brute force route of hacking. Can it be done? Not by average players. But that doesn’t mean it hasn’t happened, as you’ll see next.

Cheating a Random Number Generator

What would you do if you had access to the source code of an RNG and the skills to hack it?

Go on, you can admit it. You know you would use it to your advantage. It’s human nature, and the casinos are good for it, anyhow!

Well, Ronald Harris was in just such a privileged position, and he did just that. He worked high up in the Nevada Gaming Control Board, and through his position, he gained access to the algorithms which control casino game outcomes.

His job was to detect bugs and fix them, but he decided to follow another path. He altered the source codes so that they would pay out when a specific sequence and number of coins were fed into the machine.

Harris and an accomplice stole thousands over the years but were eventually rumbled when Harris decided to run the same con on keno games. This time, he built a program which could determine what number the program would pick next by replicating its algorithm.

What he didn’t factor into his algorithm was the sharp instincts of casino security. His accomplice was arrested and spilled the beans. Harris was sentenced to seven years in jail. He only served two.

Legendary author Oscar Wilde once said, “I can resist everything except temptation.” We’ll bet even the best of us would succumb to this one!

Why Understanding RNGs Matters

RNGs keep electronic casino games fair. Whether in a land-based casino in Vegas or in an online casino, they’re the driving force behind keeping these games random, or at least random enough for us to consider them fair.

Once you understand them, which you hopefully do by now, you’ll:

  • Understand that online casinos aren’t cheating you. If you get unlucky and lose several hands in a row against a digital machine, it’s just the RNG at work. No matter how suspicious it seems, if you’re playing at a trustworthy online casino, you aren’t being screwed
  • Understand that, for all practical purposes, you can’t cheat slot machines and other casino games. Unless you have access to the seed numbers and algorithms and are a math wizard, you have next to no chance of beating a random number generator
  • Enjoy games more. While you can definitely increase your odds by using effective blackjack strategies, for example, at the end of the day, you’re at the mercy of the math. The house always has a slight edge. You can reduce it by picking the right game and playing smart, but it’s there nonetheless

Common Questions About RNGs

Q. How do I know I can trust a random number generator?

Since you don’t have access to the algorithm, you have to rely on third parties to verify fairness. This is where organizations like eCOGRA come into play. They’re considered the gold standard when it comes to testing online casino games for fairness.

Q. How do these third parties test random number generators?

They play the thousands of hands/spins on the games and record the results, then subject them to statistical analysis. They also inspect the algorithms to ensure there are no cheats coded into them.

Q. Do land-based casinos also use RNGs?

Yes, they do. Ever since the introduction of electronic slot machines, RNGs have been used to determine outcomes.

Q. I feel I’ve been cheated at a casino which has a rigged RNG. Can I report it?

Some casinos do enter into dispute resolutions with independent adjudication services such as IBAS. This handles lots of disputes in the UK, and there are many other equivalent organizations around the world. Some casinos refuse to, though. You can always report them to the authority which has issued its license. With enough complaints, someone will investigate them.

Q. Can you recommend some trustworthy online casinos with RNGs which have been verified fair?

Sure! In fact, we’ve reviewed hundreds of them right here on! Take a look at our casino reviews to find fair, trusted sites with trustworthy algorithms.