A Beginner’s Guide to Random Number Generators in Casinos

by Tim | Dec 22, 2022

A Beginner’s Guide to Random Number Generators in Casinos

Given the nature of house edges and return to player percentages, many players may rightly wonder if casino games are truly fair or random. This is where random number generators (RNGs) come in. We’ve put together a comprehensive guide to RNGs to show you how they keep casino games, such as online slots in the UK fair and unpredictable.

Why should casino games be random?

Even though many casino games reward skill, they are still widely considered games of chance. Simply put, this means that chance or luck should decide whether you win or lose a game. The results have to be random and not predetermined. When you turn a card or roll a dice, you can’t predict what will happen and the outcome is truly random. Some aspects of casino games allow you to improve your chances of winning by, for instance, deciding when to hit or stand in a blackjack round. But the element of luck is always present and even a blackjack master can never be certain what card will be dealt next from the shuffled deck. 

The reason why people play casino games is precisely because the results are unpredictable. This means they have a real chance of winning every time. If the random or unpredictable element is removed from the game, you no longer have a fair chance to win. RNGs work to ensure that a casino isn’t deciding the outcome of every game. They do this by using an algorithm to guarantee that results are random while nonetheless factoring in the house edge. So what are RNGs, and how do they work?

What are random number generators?

Simply put, an RNG is a computer program that generates random numbers which become outcomes or results. These programs or algorithms produce sequences of numbers every second and they can be “asked” to provide a single number from this sequence at any given moment. The number it produces is your outcome, which can be the symbol on a reel, a card you draw or the result of a dice throw.  

Are RNGs truly random?

The truth is that computer-generated number sequences can never be truly random. Computers use a pattern, instruction, or algorithm to produce the sequence of numbers. Still, the RNGs being used today are incredibly sophisticated and almost impossible to hack or decipher. They produce independent sequences that give players fair results and are also required to pass audits and checks by regulatory and licensing boards. 

Are casino random number generators rigged?

Casinos don’t use number generators to cheat. On the contrary, these programs make sure that games are fair. Players should always remember that RNGs take into consideration the casino house edge. While casino games are not rigged, the casino necessarily has to have some kind of advantage to make sure that it generates sufficient profit to stay in business. The house edge percentage tells players how much the casino gets back on all wagers in the long run. It doesn’t mean every bet will pay that amount to the casino, but that this is the percentage the casino earns from all bets placed by all players. 

The RNG produces results that take this percentage into account. Because they already make a set amount of profit regardless of whether you win or lose, a casino has no reason to rig games or cheat customers. Offering fair games and having their RNGs tested improve a casino operator’s reputation and attract more customers and players.

How do casinos use random number generators online and offline?

A series of random numbers connected by lines against a background of dark space.

In some casino games, you don’t have a dealer shuffling cards to make sure results are random. This is when casinos use RNGs to produce random results. In land-based casinos, slot machines and video poker games use random number generators which generate numbers all the time, even when no one is playing. When you stop the reels, the RNG produces a number that converts into the result.

In online casinos, RNGs can be used as automated shufflers in card games or for activities such as flipping a coin. Every time you play an online slot in the UK, you interact with an RNG program. Like land-based slot machine RNGs, the RNG used by online casinos constantly produces numbers that translate into different game elements or results when the game is played.

RNGs are not limited to slots. They are also used in card games, roulette wheels, and dice games. If you’re playing live dealer casino games such as poker or roulette, number generators aren’t necessary. A real professional dealer will run the game in real time.  

How RNGs work in slot machines

To demonstrate how numbers generated by an RNG translate into game results, let’s use a three-reel slot with 10 symbols on every reel. In this game, the live number generator will assign a value to each symbol. The generator will randomly select a number between 1 and 10 for each of the three reels. These three numbers will be completely independent. The three numbers the program generates will become the three symbols that land on your reels.

Can you beat a random number generator?

Only an advanced hacker with access to the right software and algorithm tools can beat an RNG program. Game producers and developers protect information about their RNGs so that their games can only be won fairly. 

The average player will not beat the number generator, and they shouldn’t want to. The random and unpredictable nature of casino games is a key part of what makes them fun and enjoyable. Responsible players research strategies, odds and the casino edge of every game they play, but they also accept the necessary element of luck or chance that comes with betting. 

In skill-based games such as poker or blackjack, you can improve your chances of winning by mastering game strategy. Alternatively, you can also play games that have the highest winning odds and lowest house edge. But the RNG isn’t something you need to beat. It’s there to protect you from being cheated or from getting unfair results. 

How do I know an RNG is fair?

All licensed and regulated casinos are tested. If you’re playing at a reputable site, you can be sure regulatory bodies have hired third-party companies to run fairness tests to assess the RNGs being used. Fairness testing companies generate millions of results or spins in a game to see if the results are fair and if the house edge has not been raised. The Phone Casino is regulated by both the UK Gambling Commission and the Alderney Gambling Commission. Not only are our RNGs tested, but our website is checked to verify that user information is encrypted and the platform is safe and secure. 

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