A random number generator (RNG) is the algorithm that decides the results of every digital casino game. Online slots, virtual table games, video poker titles, crash games, and arcade-style games are all powered by RNGs.
We’ll explain what an RNG is and how casino sites use this technology. You’ll also learn how to check whether the RNGs have been independently certified for fairness and accuracy.
What Does an RNG Do?
An RNG produces random, unpredictable outcomes for online casino games. These algorithms constantly generate thousands of numbers each second, even when nobody is playing the games.
Each number corresponds to a specific result – which pocket a roulette ball lands in, the symbols that appear on a slot’s grid, the cards dealt in a blackjack game, and so on. The precise number generated when you hit the “Play” button determines the result.
RNGs don’t just power casino games. These are some of the other ways that RNGs are used:
- Cybersecurity and cryptography: RNGs generate the encryption keys, passwords, session tokens, and 2FA codes that secure online banking, messaging, and pretty much all encrypted internet traffic.
- Video games: Loot drops, enemy behavior, procedural map and level generation, and card shuffles in digital card games are all run by RNGs.
- Scientific and statistical work: RNGs power Monte Carlo simulations, modeling, and random sampling for surveys and studies.
- Machine learning: Developers use RNGs to shuffle training data, initialize models, and so on.
- Lotteries and raffles: RNGs ensure the results of prize draws are random and unpredictable.
How RNGs Work
An RNG produces a constant, high-speed stream of numbers, each one tied to a possible game outcome. The instant you press “Play,” it takes the next number in the stream and turns it into your result. Because the numbers pour out thousands of times a second and never settle into a pattern, nobody can predict the next result.
You might see casino RNGs described as “pseudo-random.” That’s simply the technical term for numbers generated by a formula, and it makes no practical difference to you, as the results are still impossible to predict. Independent testing labs exist to prove that, as explained in the next section.
The technology behind an RNG is highly sophisticated, but what it delivers is refreshingly simple. Every spin, dice roll, or draw is decided at random, and nobody can manipulate the results.
How RNGs Are Tested and Certified
You don’t simply need to trust the RNGs to deliver fair, accurate results. Before a game goes live at a licensed casino, its RNG is tested and certified by independent labs.
The most famous labs are eCOGRA, iTech Labs, Gaming Laboratories International (GLI), BMM Testlabs, and Quinel. They put an RNG through a rigorous series of tests, examining millions of outcomes to confirm the results are evenly distributed, statistically random, and impossible to predict.
They also check that each game pays out at its stated return to player (RTP) rate, and they review the underlying code for flaws.
A game will only receive a certification after passing these tests. Licensed casinos are required to host games with certified RNGs, and many display their testing seals openly.
If you stick to games from reputable software providers, you can rest assured that their RNGs have been independently audited and certified for fairness. For example, GLI and Quinel test slots from Pragmatic Play, while NetEnt slots are certified by iTech Labs, GLI, and eCOGRA. These games have a house edge, but the results aren’t rigged, as every outcome is completely random.
RNG vs Provably Fair
For many years, all digital casino games used standard RNGs. However, some crypto casino games now use an intriguing alternative: Provably Fair technology.
They both aim to deliver fair results, but they earn your trust in different ways:
- Random Number Generators: The RNG runs on the casino’s servers, and you rely on independent labs to confirm that it’s fair. You can’t personally check any individual spin. It’s a model built on third-party trust, but it works well at licensed casinos.
- Provably Fair: These games use cryptography to let you personally verify the fairness of each result. Before you bet, the casino shows you a hashed seed – a scrambled code that it can’t change. You add your own seed, and when the round ends, the casino reveals the original seed, letting you confirm that the result wasn’t manipulated.
Just bear in mind that even the best crypto casinos only host a handful of Provably Fair games. They include variety games like Plinko, Crash, Dice, and Mines, plus a small selection of slots and virtual table games from providers like BGaming. The vast majority of casino games run on standard RNGs.
RNG Myths Debunked
- “I’m due a win after a losing streak.” Unfortunately, you aren’t. An RNG has no memory, so every result is independent. Just because a slot hasn’t paid out for a while, that doesn’t mean the next spin is more likely to produce a winning combo.
- “The casino tightens the game when I’m winning.” A certified RNG can’t be adjusted on the fly or aimed at individual players. Its behavior is fixed and independently audited.
- “You can beat an RNG with the right timing or betting pattern.” You can’t. The outcomes are genuinely unpredictable, so following a system, riding a hot streak, or betting at a certain time of day won’t improve your odds.
Where RNGs Aren’t Used
RNGs don’t power the results on live dealer games. These games let you connect with a real dealer, who will be based in a studio or at a physical casino.
There’s no need to use an RNG, as the dealers use physical equipment – cards, dice, roulette wheels, and so on. The results unfold in real time, and you watch the action on your screen.
However, some live dealer games feature random multipliers. Examples include Lightning Roulette and Quantum Roulette. In that case, the providers use RNGs to determine which bets or segments benefit from multipliers. RNGs also power the animated bonus rounds on certain live dealer games, such as Funky Time and Monopoly Live.
Independent testing labs certify those RNGs, and they also test the equipment and monitor the games to ensure the results are fair.
Conclusion
An RNG is the powerful engine that quietly powers fair online casino games. Every result is decided at random, so nobody can predict or manipulate the outcome. Just stick to licensed casinos that host independently certified games, and you can play with confidence.
FAQs
No, casino RNGs aren’t rigged if you play games from reputable software providers like NetEnt, Pragmatic Play, and Hacksaw Gaming. Their RNGs are independently certified for fairness and accuracy, so you can rely on them to deliver genuinely random, unpredictable results.
Independent auditors at specialist testing labs evaluate casino RNG algorithms. The leading labs that test casino RNGs include eCOGRA, BMM Testlabs, iTech Labs, and GLI. They’re all independent, well-established companies with trusted reputations.
No, it’s impossible to predict which number an RNG will produce. When you understand how an RNG works, you’ll realize that you can’t guess what number will appear at the precise millisecond you press “Play.” Because licensed casinos only host games with independently certified RNGs, that unpredictability comes with a guarantee of fairness.
Ilija is a CCN writer with 7 years of experience covering all things crypto. Ever since a fateful run-in with Litecoin in 2013, he's been an avid investor and writer in the space. When he's not maniacally hacking away at his keyboard, Ilija spends his time either hiking in nature or holed up in his apartment gaming.
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