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RNG – Random Number Generator

All online casinos are using Random Number Generators, or for short RNG, to determine the outcome of their games. Most commonly this technology can be found in slot machines but is also used for table games, scratch cards, and other games. First, it is important to clarify the term “Random” before we start talking about the Random Number Generator. Randomness means that it is impossible or very difficult to predict in advance what the outcome of a particular action will be. In the case of casino games, this is, for example, predicting the next card that appears on the table, or the symbols for a spin in a video slot.

How Does a Random Number Generator Work?

At online casinos, but also at video slots in physical casinos, Random Number Generators are used to get the most random result possible. An RNG can be software and/or hardware. When it comes to a software-driven RNG, we speak of a Pseudo-Random Number Generator, which we will also cover in this expert iGaming guide

A hardware-driven RNG works by including certain external factors in determining a random sequence of numbers. This can be, for example, the temperature, atmospheric pressure, or the amount of a particular substance in the air. This factor gives a series of binary numbers that are converted through an algorithm into a particular move or card in a casino game. This is an optimally randomized method because it cannot be influenced and the factor is always different.

In addition, it is practically impossible to crack or hack a hardware RNG. This is because, firstly, the measured factor or factors is/are often secret. Second, it is impossible to know, for example, the amount of carbon in an online casino data center at a specified time. Third, the correct algorithm and operation of this sequence have yet to be discovered before predicting a move, outcome, or card. The disadvantage of a hardware RNG is that more processing time is required and therefore it works less quickly.

RNGs Ensure Fairness and Random Outcomes

The RNG also ensures that the chance of a win occurring is the same in every game round. For example, if you just finished a bonus round with free spins, the chances of the next spin triggering another round of free spins are just the same as they are a hundred spins later. In many ways, an RNG works like tossing a dice. For every toss, the chances of you getting six are the same, no matter what happened in the last toss.

Even though the games themselves are fair, you should always remember that they're fair in the sense that they work as intended. That being said, a slot machine is never designed to pay out all the bets it gets as winnings since the RTP is set to less than 100%. After all, the casino also has to make money somehow. In terms of slots, therefore, what fair means in the fair-gaming sense is that you're not at a disadvantage compared to other players. But, you will be at a disadvantage compared to the casino. This is why cashing out big wins is so important.

What is a Pseudo-Random Number Generator?

A Pseudo-Random Number Generator works via software and, therefore, cannot measure external factors and include them in the delivery of a random result. The Pseudo RNG is built into, for example, a chip and contains an algorithm that gives a certain result at certain times based on a key or an initial value. Since this software is not linked to an external factor, it can give the most random result of a casino game much faster. An internal factor, such as a clock, could be used, however.

The software Random Number Generator is based on the key value. When someone knows this key value, it is possible to predict the outcome at a specific time. The fact that there is some form of reproducibility in it is not necessarily a disadvantage in the case of casino games unless hackers take advantage of this. Due to the much higher speed and the fact that no additional hardware needs to be built into a video slot, for example, Pseudo RNGs are widely used in casinos, both online and offline. 

How Do Casinos Provide Random Results?

There are several ways in which online and land-based casinos provide randomness. In table games, this can be done, for example, by manually shuffling the cards or by using a shuffling machine for this. This machine is made in such a way that the cards come out randomly. According to research by statisticians, you have to apply the “riffle shuffle” seven times or more or spread the cards out on the table and shuffle them together for about a minute.

At both online casinos and land-based casinos, only the live casino games work with manual randomness. The rest of the available casino games work via a (Pseudo) Random Number Generator. How this works exactly differs for each game and each game developer or online casino.

An example of a Random Number Generator comes from a well-known poker site. A semi-transparent mirror sometimes reflects the beam of a laser and sometimes it does not. A reflection gives a 1 and no reflection a 0. The second comes from the input of the players. The movements of the mouse, reaction time, clicks, and more information are converted into a binary code. By putting these numbers in order, combining them, and then passing them through an algorithm, a completely random sequence is created that can be converted into a specific card, which is then presented on the table.

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