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What Is RNG And RTP? And How Does It Affect Slots Online?

Online casinos aim to provide a gaming experience that is as close as possible to playing in a land-based casino; which is where RNG and RTP come into play.

Updated Apr 24th, 2019
Random Number Generators & Return To Player Rates
Random Number Generators & Return To Player Rates
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Therefore, the most important thing that online casinos have to get right is making sure that the games on offer behave in the same way as they do when being played on the real machines in places like Vegas and Macaw.

Casino sites often opt to use random number generators (RNG), because randomness is an integral aspect of casino games.

Because whilst we all know that the casino has an edge over the players, these machines are made to pay out enough to keep us entertained and hoping we get to be the player who takes down the house.

Here we demystify random number generators, how they affect the Return to Player Rate of a slot machine (RTP), and why it matters to you as a player.

What is a random number generator?

An RNG is a computer program that spits out results at random. Pseudorandom numbers are an alternative to “true” random numbers, with pseudo-random number generators mostly being used with casino mobile slots.

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They are unique and do not need any external input (numbers or data) to produce an output, just an algorithm and seed number.

PRNGs are efficient, as they can produce many numbers within a short time. They are also deterministic, as they can reproduce sequences of numbers at a later date if the starting point in the sequence is known.

These number generators play a crucial part in a number of online casino games, and by being independently verified as fair and accurate by third parties such as eCogra (among others), give both casinos and players peace of mind.

Why is randomness important?

Randomness is what effectively makes it possible to win at casino games, as they are known as games of chance.

This is because it is chance, or luck, that determines whether you win or lose, so the outcome of any game is always determined randomly in some way. This could be by the turn of a card, the roll of a dice, or the spin of a roulette wheel.

The whole point of playing online mobile casino games is that the results are unpredictable, as gambling is all about risking money on an uncertain outcome.

The excitement for players comes from having the chance of winning some money and facing the risk of losing, without any direct control over what is going to happen.

When are RNGs used in mobile games?

Online casinos work by using software that imitates the actions that take place in a live casino and then displays the outcomes virtually on your computer screen using graphics.What Is

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Slots are the definitive example of random number generators in practice. However, all modern online casino games use RNGs to provide the luck element of their games.

For example, when it comes to video slots, the RNG dictates the outcome of every single spin – similar to the video slots standing in casino floors, because they also work from a computer within the machine. It’s just that this time it’s online.

Whereas, if you are playing tables games such as Blackjack, the RNG works a little differently, because in a real casino you get croupiers and real cards. In table games, the RNG will feed the software a unique value which means the order of all the cards dealt in that hand are pre-determined and random.

Any time that the software needs to reproduce a random outcome, it communicates with the RNG.

Are random number generators fair?

All regulated, licensed casinos have software that has been tested by an independent third party.

These third parties offer a full range of testing and consulting to both online and brick and mortar casinos and gambling corporations.

These tests include RNG evaluations, game and mathematics evaluations, ongoing RNG or game payout verification and reporting live dealer, sports-book or betting exchange evaluations, poker system audits and full security audits.

Various casino websites have an impeccable reputation when it comes to fairness and credibility because they feature software developments in RNGs within their games.

Reputable casino software game studios will have certificates from these third parties testing their game before they even go on the casino site.

All the formulas used by an online casino’s RNG have to allow for all outcomes to be equally fair and unbiased.

With the exception of some shady casinos who have been shown to be unfair and cheat UK players out of their money, the majority of the best online slot sites out there are completely fair – when in doubt, make sure you read the casino reviews from independent media sites (*cough* Like Lucky Mobile Slots *cough*).

You can then rest assured that the games offered by reputable online casinos are trustworthy.

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Can the slot games be hacked?

Up until now, this hasn’t happened. Once at the casino, the video slots sit on the site (much like a machine in a real casino) and are protected by the same software that protects casinos from being hacked – and trust us, no one is more likely to keep money safe than a gambling house.

That said, what has happened in the past is that dodgy casinos have copied well-known games and then put them on their site, and changed the maths to suit them.

So they are not affiliated to the likes of NetEntertainment or Microgaming studios. They’ve made a cheap copy to put you at ease, and then when you play, you lose.

This is a very rare case (we know of one casino that did this, and they have since been discovered and shut down).

A good way to ensure that you stay safe is to play on casino with reputable casino licenses, like the Malta Gaming Authority or the UK Gambling Commission. In order to get either license, you need to prove fair play and that your RNG is being tested regularly by a third party.

All the casinos on our site will hold one or both of these licenses, for good reasons.

How does the RNG affect the RTP?

Known as the return to player, RTP is a percentage that a slot pays back after a theoretical number of spins. It is the term the game creators use to describe the percentage of all the wagered money a slot or casino game will pay back to players over time.

RNGs are programmed to pick certain combinations of numbers to achieve a consistent return to player (RTP) rate. Ever since September 2016, online casinos have been required to monitor the actual RTP of its games to make sure the RNG is not faulty. This is done by dividing the total value of all payouts of a machine or game by the total turnover it has increased.

Therefore, how much a player is winning and losing, in the long run, is all determined by the RTP, which is determined by the RNG.

The average percentage of RTP is generally measured over 10,000 or 100,000 games or greater for compensated and random machines respectively, dependent upon their category.

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For example, most online slot games typically have an RTP of between 95% and 98%, with the average being around 96%. We would rarely recommend you play on a machine that has less than 95% RTP, regardless of volatility.

Some of the best online slot sites often declare the RTP of each slot game (Pragmatic Play studios for example), as it is a very popular value in the online casino world, as it can be expressed as a single number. It not only illustrates a level of trustworthiness but considering that rates between casinos differ, it empowers players to choose casinos that offer the best value.

How much should I pay attention to the RTP?

Slot RTP is only one of the factors to consider when choosing a slot and should only serve as an indication of how much the game is expected to pay out.

Some players would prefer to win smaller amounts more often, while others like to aim for the biggest payouts and may be prepared to risk more in order to hit a jackpot, so slot volatility also comes into play.

Low volatility slots typically have a rather high RTP, which is why a lot of avid gamblers prefer to play medium to high variance slots with a lower RTP in order to get that bigger win.

The Return to Player Rate is just one factor to consider, but it helps to give you a sense of trust in the casino and the games.

Videoslots Casino MY RTP features is a great example of this as they not only give the theoretical RTP of the games but also the actual RTP ie. based on how much it has paid out at their casino recently.

Ultimately, it’s good to know how RNG and RTP affect online slots because then you know the trustworthy casino sites to play. But it won’t tell you whether a slot machine is fun or not.

About Lucky Mobile Slots

We are an incredibly devoted duo, who have both been involved in the casino industry for over 15 years. We want to help our readers understand what happens in the background of online casinos, by showcasing only the best online casino slots in the industry.

If you are looking to play mobile slots, we review a number of different selected casinos by highlighting their terms and conditions, payment methods, minimum deposits and the best casino bonuses in the industry.

We place a great emphasis on the games and what they provide, helping you to make an informed decision of the best slots to play online on your iPhone or Android devices.

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