What are random number generators (RNGs)? Understanding their usage in online casino gaming

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When you play a casino game, you need to know that it is fair, meaning that the outcome has to be completely random. In land-based games, this is done through a professional dealer following strict rules for dealing the cards and spinning the roulette wheel – but how is it done online?

What is a random number generator?

Commonly known as an RNG, this is a crucial part of any online casino. To put it simply, it is a piece of software that ensures that the numbers that are picked are completely random each time and don’t follow any type of pattern.

The overall idea is that the online version of a casino game is carried out with exactly the same degree of luck and randomness as a game where a human dealer is present. Casino players don’t really need to know the ins and outs of how the RNG works, but they do need to know that the site they use has this technology.

It is also important to see that the RNG is verified and is regularly tested to ensure that it is still working perfectly. A reputable casino will make the verification and continual testing of this software one of its priorities. 

A game with no RNG, or with one that is faulty in some way, would produce unreliable results that would almost certainly lead to players starting to doubt the fairness of the casino. 

How it works in a casino game

If you play in a land-based casino, you will come across the use of RNGs in automated games such as video slots. On the other hand, with online casinos, they are present in all of the games except the live dealer titles where a human dealer is shown on the screen.

Every time you click the button for a new game, the RNG will kick into action. This means that it will create a new, unique series of numbers that determines the cards you are dealt or the symbols that appear on your slot machine. On the roulette table, this is what decides where the ball will come to rest.

Of course, it all happens so fast that players don’t even notice the series of complex calculations that are going on in the background. There is normally no delay at all between hitting the button and the action taking place on the screen.  

Resorts Casino counts among the best NJ online casinos, with fair and responsible gaming high on its list of issues covered in the terms and conditions. We can see on its site that numerous slots, card games and table games can be all be played with an RNG controlling the action at all times.


The RNG is possibly the most important part of any online casino these days, but players don’t need to really know much about it. As long as they keep seeing fair, random results, they will know that the games are safe to play.