If you’ve ever wondered how online casino games – including those at NetBet – generate results, the answer for many digital casino games involves a Random Number Generator, commonly shortened to RNG.
RNG technology is used to generate random outcomes in games such as online slots, blackjack and roulette. It is a fundamental part of how many online casino games operate because randomness helps ensure that individual outcomes cannot simply be predicted or manually selected.
But what exactly is an RNG, how does it work and why is randomness so important?
What Is RNG?
RNG stands for Random Number Generator. An RNG is a system designed to produce a sequence of values that behaves randomly according to the requirements of the game.
In an online casino, the RNG can be used as part of the process that determines the outcome of a game.
For example, in a slot, the RNG can determine the result of a spin. In an RNG-based blackjack game, it can determine the cards dealt. In an online roulette game, it can determine the winning number.
The precise implementation depends on the game.
How Does a Random Number Generator Work?
Many online casino RNGs are software-based systems known as pseudo-random number generators (PRNGs).
The term “pseudo-random” doesn’t mean the results are simply predictable. Rather, the system uses an algorithm to generate a sequence of values that has the statistical properties required for randomness.
The system can generate numbers extremely quickly, meaning a new result can be produced whenever the game requires one.
The resulting number is then mapped to the relevant game outcome.
For a slot, that could mean determining which symbols appear. For a card game, it could form part of the process used to shuffle or select cards.
Why Is Randomness Important at Online Casinos?
Randomness is essential because players should not be able to predict or influence individual game outcomes.
If a game weren’t sufficiently random, players could potentially identify patterns or exploit predictable behaviour.
A properly tested RNG is designed to ensure that outcomes are appropriately distributed and that there isn’t an intentional bias towards particular results.
Gaming Laboratories International (GLI) describes RNG testing as a key part of iGaming systems where RNGs determine game outcomes, with testing designed to assess non-predictability and potential bias.
How Do Online Slots Use RNG?
RNG technology is particularly important for online slots.
When you click the spin button, the game needs to determine the outcome of that spin. The RNG provides the underlying random value used by the game’s mathematical model.
That value is then translated into the game’s result according to its programmed reel configuration, symbols, paytable and other rules.
This means that pressing the spin button isn’t choosing between a set of pre-selected results. The game’s RNG and mathematical model determine the outcome.
You can explore the selection of slots available at NetBet to see how different games use their own themes, features and mathematical models.
How Does RNG Work in Online Blackjack?
RNG blackjack uses randomised software rather than physical cards.
The RNG can determine which cards are dealt, with the game applying the relevant rules to determine the hand’s outcome.
This differs from live blackjack, where a real dealer handles physical cards. In a live game, the physical deck and dealing process provide the source of randomness rather than a digital RNG determining every card.
Both formats can provide a blackjack experience, but they operate differently behind the scenes.
Does RNG Mean Every Outcome Is Completely Random?
RNG testing is about more than simply asking whether numbers “look random”.
Independent testing can examine the underlying algorithm, implementation and statistical behaviour of the results.
GLI’s published RNG requirements include source-code review and statistical analysis designed to assess factors such as distribution and independence. Its interactive-gaming standards also describe testing for statistical independence, fair distribution and recognised statistical tests.
The purpose is to establish that the RNG performs according to the applicable technical requirements.
How Are Casino RNGs Tested?
Independent laboratories can test RNG systems using large amounts of generated data and statistical analysis.
Testing can include examining:
- The RNG algorithm
- Source code
- Random-number distribution
- Statistical independence
- Scaling and mapping processes
- Game implementation
- Potential sources of bias
- The relationship between RNG output and game outcomes
GLI states that its RNG testing methodology covers software-based, hardware and hybrid RNG systems.
Testing can also take place alongside broader game testing, including RTP and game mathematics analysis. GLI lists both RNG testing and percentage Return to Player analysis among its digital and iGaming testing services.
Does RNG Guarantee That You Will Win?
No, not at all. This is a very important thing to learn/take on board.
A random game can still have a mathematical house edge. RNG ensures that individual outcomes are generated according to the game’s randomisation requirements; it doesn’t change the game’s payout structure.
For example, a slot might have a theoretical RTP of 96%. That doesn’t mean the RNG will ensure that every player receives €96 for every €100 wagered.
The RTP is a long-term mathematical expectation. Individual sessions can produce results that are significantly higher or lower.
Similarly, if a roulette wheel has landed on red several times, the RNG doesn’t make black “due” on the next spin.
Can You Predict an RNG Casino Game?
A properly designed and tested RNG is intended to make individual outcomes unpredictable.
That means strategies based on previous results generally cannot predict the next outcome.
For example, seeing a particular slot symbol appear several times doesn’t mean that another symbol is now due. Likewise, a sequence of roulette results doesn’t create a guaranteed prediction about the next spin.
Randomness means previous results don’t provide a simple formula for determining the next result.
RNG and Casino Fairness
RNG is one part of the wider framework used to establish the integrity of online casino games.
Game mathematics, RTP, payout structures and software can also be tested. Independent testing helps establish that the game behaves according to its intended design.
This is why RNG is closely connected to the broader question of casino fairness. For players, it means the randomness behind digital games can be independently assessed rather than simply being accepted on trust.
Our brilliant guide on How casino games are tested for fairness provides even more information on the matter.
Explore RNG Casino Games at NetBet Casino!
Now that you know what RNG means and why randomness matters, you can explore a range of online casino games at NetBet.
If slots are your preference, browse the available online slots. You can also explore table games and see the different formats available.
Remember that RNG ensures game outcomes are generated according to the game’s randomisation system, but it cannot guarantee a particular result. Casino games involve risk, so always play responsibly and within your limits.
Before you begin playing, decide on a budget, take regular breaks and enjoy your gaming responsibly. NetBet Casino also offers a comprehensive range of Safer Gambling tools, including deposit limits, reality checks and cooling-off periods, helping players stay in control while enjoying their favourite games.
