What is Random Number Generator Software and How Does it Work?

The concept of using random numbers in science isn’t new. Randomness is used to pick subjects, to determine where to start or which data to use for specific purposes. In the casino industry, randomness   is how casinos make money.

It’s also how players know games like slots and roulette are fair. To be clear, random number generator software doesn’t precisely mean a great is great. Continue reading to discover more.

What is Random Number Generator (RNG) Software?

A random number generator (RNG) is a computer program which produces random winners at games of chance like slots, video poker and roulette. RNG software uses an algorithm to run numbers continuously before picking the winning number entirely at random.

With slots and roulette, you can determine when to spin the reels/wheels and when to stop the spinning. But this doesn’t mean you can influence the outcome. All you have is a sense of control.

In reality, RNG software determines your fate:

  • Whether you win or lose
  • How often you win
  • Whether you trigger a bonus round or a wild

How Does RNG Software Work?

RNG Software works through one of two ways: True Randomness or Pseudo randomness.

  1. Pseudo Random RNG Software

Pseudo random RNG software depends on computer algorithms to produce fairly random outcomes. To expound more, the process of creating a random outcome starts with something known as a seed key.

In the casino business, software developers create and own the seed keys used in slots and other games of chance. Developers use pseudo random RNG software because it’s faster and more effective in scenarios where a series of events are repeated regularly—playing slots and roulette.

Is RNG software used at US online casino sites? Yes, it’s used. In fact, a list of US operators with fair RNG games can be found here. The games range from slots and jackpots to RNG blackjack and roulette.

  1. Truly Random RNG Software

Truly random RNG software base its outcome on results that are entirely difficult to predict. Think of lightning occurrences.

According to scientists, about 100 lightning flashes happen every second. However, no one can predict exactly when each flash takes place. Some RNG software use data obtained through lightning flashes to generate entirely random numbers.

Another way RNG software create random numbers is by using data generated from the process of radioactive decay. The process takes years and happens through a truly random nature.

Are RNG Software Games Fair?                     

Generally speaking, RNG software games are safe and fair. You can’t rig them and neither can the casinos. There’s a caveat: there are a myriad of factors that determine whether games are fair or rigged.

For starters, is the casino licensed? Does it provide games from trustworthy software providers?  A casino that meets the criteria mentioned above is most likely to provide fair games.

By comparison, a casino with no license and offers games from unknown software developers can’t guarantee fair games. It’s even worse when the operator isn’t reputable.

Is RNG Software Everything in Casino Games?

There’s no doubt RNG software is important in ensuring casino games are fair. But it’s not the only thing you need to check in a game. To play high-quality, high-paying casino games, check for the following features:

  • Return to Player (RTP)

Return to Player (RTP) describes the average amount of money a game pays back to players over time. It’s often expressed as a percentage. So, a game with a 95% RTP pays back 95% of gambled money to winners. The remaining 5% is the casino’s guaranteed profit.

Every game that uses RNG software has a known RTP. For slots, RTPs range from 85% for low-paying games to 99% for the best-paying slots. In blackjack, the RTP stands at 99%. In video poker, it varies between 95% and 103%.

  • Betting Limits

Some casino games have different payout rates depending on the amount of money you bet. If you wager cents, the game lowers its RTP. But if you bet like a high roller, the return to player is increased.

An example is NetEnt’s Guns N’ Roses. It has a default RTP of 97%, which is impressive. However, its RTP can be adjusted downwards or upwards depending on whether you’re wagering maximum or minimum amounts.

  • In-Game Features

In-game technology features like wilds and scatters can also determine how often you win in a slot. Picture this. A game has a scatter symbol that activates a bonus round and free spins. Additionally, it has a wild that converts all other icons into winning symbols.

What’s more, the game has an avalanche feature and a multiplier. By comparison, there’s a slot with no scatters and symbols. All it has are a few winning symbols. The first game is likely to help you win more often than the latter.

  • Variance/Volatility

Variance is the frequency through which a casino game pays out. It doesn’t matter whether has a game has RNG software or not. Every casino game has volatility—low, medium or high variance.

Low variance slots tend to payout more often than medium and high-variance slots. However, they payout in small amounts. On the other hand, high-volatility slots payout in bigger amounts but less often than low-volatility games.

  • Jackpots

The presence of a jackpot in a slot can influence whether you win or lose in a slot. Think about it. Many slots with progressive jackpots have lower RTPs than games without jackpots. But if you’re lucky, a progressive jackpot can help you win a life changing amount of money.

Progressive jackpots aside, many slots have random jackpots. They can help you win a decent amount of cash but not as much money as progressive slots.


RNG software is a computer algorithm used to produce winning symbols or numbers in casino games. Not all games use random number generators to produce winners. But slots and some blackjack, roulette and poker games use the software. It’s essential because it shows a game is fair. However, it’s just one of several things that determine the quality of casino games.

Nathaniel Villa
Nathaniel Villa