Random Number Generators (RNGs)

Unraveling the Mystery of RNGs in Casinos: Game Mechanics to Fair Play

By Nick Gough, Gambling Expert with over 20 years of experience.

The allure of casinos lies in the unpredictable nature of their games, whether it’s the spin of a roulette wheel or the roll of the dice. At the heart of this unpredictability in modern casinos is a technology known as the Random Number Generator (RNG). With over two decades in the gambling industry, I’ve observed and understood the essential role RNGs play in ensuring a genuine, thrilling, and fair gambling experience. Let’s take a historical and analytical journey to understand RNGs better.

The History of Random Number Generators

Long before the digital age, randomness in games was determined by physical objects like dice, wheels, or shuffled cards. As the gaming world transitioned to electronic and online platforms in the latter half of the 20th century, there arose a need to simulate this randomness digitally. Enter the RNG.

The earliest computer RNGs in the 1960s and 1970s were algorithm-based, and while they did a decent job, the demand for more unpredictability led to the development of more advanced RNGs, using intricate algorithms and external inputs like atmospheric noise.

How do They Work in Casinos?

In a casino context, RNGs work as the brain behind every electronic game, be it a digital slot machine or an online poker game. They continuously produce a series of numbers, even when the game isn’t being played. When you press the ‘spin’ button on a slot machine, for example, the RNG provides a random number that determines the outcome.

These numbers can range from 0 to several billion. The software in the game then translates this number into a specific outcome – like a combination of symbols on a slot machine.

Slot Machines Also Use Random Number Generators

Random Number Generator in Slots Icon


Modern slot machines heavily rely on RNGs. The days of mechanically-timed slots are long gone. When you’re playing a slot today, the outcome is determined by a split-second RNG calculation, ensuring that each spin’s outcome is independent of the last.

Are Slots 100% Random?

This is a question I’ve fielded often in my years in the industry. Technically speaking, the algorithm-based RNGs used in casino games are known as pseudo-random number generators. This means that while they use complex algorithms to produce outcomes that are nearly impossible to predict, they aren’t purely random in a natural sense. However, for all practical and gaming purposes, they are indistinguishable from true randomness.

However, a Slot Machines RTP also affects how much you win back in the long run. Furthermore, slots volatility also affects if you often win. For example, a high volatile slot machine will pay less frequently but more often bigger wins.

List of Casino Games That Are Random

Casino games relying solely on Random Number Generators (RNGs) generally don’t incorporate player skill or strategy. They’re games of pure chance. Here’s a list of casino games that are primarily RNG-based:

  1. Slot Machines: These are the most common RNG-based games. Modern slot machines use software and RNGs to determine the outcome of each spin.
  2. Electronic Bingo Machines: The numbers drawn in these bingo machines are determined by RNGs.
  3. Keno: In electronic keno games, the numbers drawn are determined by RNG.
  4. Electronic Roulette: In some casinos, roulette versions don’t involve a physical ball or wheel but use RNG to determine the outcome.
  5. Electronic Table Games: Some casinos have electronic versions of games where the outcome is determined by RNG instead of physical dice or cards.
  6. Instant Win Scratch Cards Online: While physical scratch cards are pre-printed with an outcome, online versions often use RNGs to decide the result.
  7. Online Lottery Drawings: Online lotteries can use RNGs to select the winning numbers.
  8. Virtual Racing and Sports: These are simulated races or sports games where RNG determines the outcome.

Understanding that the RNG in legitimate casinos is unpredictable and fair is essential. Casinos are typically subject to regulations to ensure their RNGs are random and no

Casino Games That Are Not Total Random

In the world of casinos, there’s a blend of games of chance and games of skill. While many casino games are rooted in randomness, there are some that offer players more control over the outcome through strategy. However, it’s essential to understand that even in games of skill, there’s still an element of chance involved. Here are some of the primary casino games where skill can play a part, reducing the level of randomness:

  1. Poker: Perhaps the most notable example of a game where skill matters significantly. While the cards you’re dealt are random, how you play them – the decisions you make, the strategies you adopt, your ability to read other players – has a profound impact on the game’s outcome. Over time, skilled poker players tend to win more than they lose.
  2. Blackjack: While the cards dealt are random, players can use strategies like card counting (although frowned upon by casinos and often leading to players being asked to leave or barred) and basic blackjack strategy to reduce the house edge.
  3. Video Poker: Similar to slot machines in appearance, video poker allows for decision-making that can influence the outcome. Players can decide which cards to hold and which to discard, leading to multiple potential outcomes.
  4. Sports Betting: While still containing elements of unpredictability, a bettor’s knowledge of the sport, teams, players, and other factors can increase the chances of making a successful bet.
  5. Horse Race Betting: Similar to sports betting, understanding the horses, their past performances, the jockeys, and track conditions can influence betting decisions.
  6. Craps: While the roll of the dice is random, players can adopt betting strategies to manage their bankrolls better and to bet in ways that align with their risk preferences.
  7. Baccarat: Though largely a game of chance, players can decide whether to bet on the banker, player, or a tie. Each of these options comes with different odds, and understanding these can influence a player’s decisions.

However, even with these games, it’s essential to remember a few things:

  • House Edge: No matter how skilled a player you are, the casino always has a slight advantage known as the “house edge.” Some strategies can minimize this edge, but it’s challenging to eliminate it entirely.
  • Chance Element: Even in games of skill, there’s always a degree of randomness involved. For instance, no matter how well you understand horse racing, unexpected events can still lead to surprising results.
  • Responsible Gambling: Whether playing games of chance or skill, it’s crucial always to gamble responsibly. Knowing when to stop is as vital as any strategy you employ.

While many casino games incorporate randomness, some allow for skill and strategy to play a significant role in the outcome. This blend of unpredictability and control is what makes casino gaming so endlessly fascinating for many.

How RNGs Influence Player Behavior

From my observations, most regular casino-goers have an inherent trust in the RNG system, but they also have superstitions. Some believe that machines have ‘hot’ or ‘cold’ streaks, despite the independent nature of each spin or hand. As an expert, I can confirm that each game outcome is entirely disconnected from the last, but these beliefs highlight the human need to find patterns, even in the realms of pure chance.

The Future of RNG in Casinos

Future CasinoHaving witnessed the evolution of RNGs in my twenty years in the industry, I anticipate further advancements in the coming decade. As quantum computing becomes more accessible, we may see the birth of quantum random number generators in casinos. Quantum RNGs, unlike their algorithmic counterparts, harness the inherent unpredictability of quantum mechanics, potentially offering a higher degree of randomness.

The Ethics of RNGs

With the implementation of RNGs, casinos have taken a massive step towards ensuring ethical gameplay. By removing the potential for machines to be rigged, and by committing to regular audits by external agencies, casinos show their dedication to fair play. However, responsible gambling doesn’t stop there. It’s crucial for players to understand the nature of RNGs – that there’s no predictability or pattern. This can prevent chasing losses based on the mistaken belief that a win is “due” soon.

Player Tips Regarding RNGs

Player Tips IconAlways Remember the Independence of Events: Just because a number or symbol hasn’t appeared for a while doesn’t mean it’s due to appear soon. Each event is independent, and past outcomes do not influence future ones.

  • Choose Certified Casinos: Always play at casinos that have their RNGs certified by recognized bodies. This ensures fairness and transparency.
  • Stay Informed: The more you know about how games work, the better equipped you are to play responsibly. If a strategy or tip sounds too good to be true, it likely is.

In casino games that allow for strategies to reduce the house edge, it’s advisable to employ them.” In my many years of gaming can ensure it makes a difference in how much you win or lose.

RNGs represent a remarkable fusion of technology and gaming, ensuring unpredictability and fairness in casino games. Their omnipresence in modern casinos underscores a commitment to ethical gaming standards, delivering an experience that’s both thrilling and just. As the world of gambling continues to evolve, the role of RNGs will undeniably remain pivotal, guiding both players and industry professionals towards a transparent and exhilarating gaming journey.

Why RNG Ensure Fair Play at Casinos

RNGs are vital for fair play. When properly implemented, they ensure that games aren’t rigged and that players have an equal chance of winning. Regulatory bodies in the gambling industry often require casinos to have their RNGs tested and certified by independent third-party agencies. This ensures that outcomes are as unpredictable as possible, reflecting a game of chance rather than manipulation.


What’s the Most Popular Random Number People Play in Casinos?

Interestingly, while RNGs deal with billions of numbers, humans have their biases. In games like roulette, for instance, 17 is often cited as one of the most commonly played numbers, possibly due to its central position on the table1. However, it’s worth noting that each spin is independent, and past spins don’t influence future outcomes.

Can a RNG Get Hacked?

With the growing sophistication of technology, hacking concerns have naturally arisen. While it’s theoretically possible to hack into anything digital, reputable casinos invest heavily in cybersecurity measures. RNGs are designed to be unpredictable, and when combined with strong encryption methods and regular security audits, the likelihood of successful hacks is extremely minimal.

In conclusion, RNGs have transformed the gambling industry, ensuring that the thrill of unpredictability remains, even in a digital age. They level the playing field, ensuring that every player, novice or seasoned, gets an equal shot at the jackpot. Here’s to the joy of the unexpected!

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The Gambler’s Fallacy and the Hot Hand: Empirical Data from Casinos”, Journal of Risk and Uncertainty, 1993.  PDF

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