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Slot mechanics – how do online slots work?

If you’ve ever played slots at all, you may have wondered how slots machines work. What determines whether you’ll win or lose on your next spin, and what triggers that juicy bonus? Can you trust their mechanism? What does RNG mean?

Understanding how slot machines work can help you make better decisions with regard to the games you choose to play. In this article, we’ll briefly outline how online slots work by discussing factors like slot hit rate, slot volatility and the random number generator.

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What does RNG mean?

RNG, or random number generator, is what decides the result of a spin, and is crucial to understand how slot machines work. The outcomes of your slot spins are not pre-programmed, and do not depend on your previous spins. Instead, they are determined by complex mathematical equations thanks to a random number generator. The RNG is a software program that randomizes all possible outcomes. Explained in simple terms, as soon as you press the spin button, the RNG assigns random numbers to the reels, and the reels will stop depending on the numbers that have been generated. This means that even if the reels are still spinning, the outcome has already been decided and is determined by the exact second you have pressed the spin button.

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The software of the Random Number Generator is tested and certified to ensure that its outcomes are not manipulated, ensuring that these will remain totally random. So if you’ve been wondering if slots are rigged, you may rest assured that the ones created by licensed game providers and which you’ll find at secure UK online casinos are definitely not rigged!

Slot hit rate and volatility

Of course, every slot is programmed a bit differently and the outcomes for each game are generated by a different random number generator. For this reason, you’ll come across terms like slot hit rate and slot volatility when you're trying to find out how individual slot machines work. These terms are interrelated and refer to the payout structure of the game.

Slot hit rate means how often you can expect to land on a winning combination. To put it simply, slots with a 25% hit rate would result in one winning spin out of every four (on average). A slot with a high hit rate can be more entertaining and encouraging, but not necessarily more rewarding. This is because hit rate doesn’t take into consideration whether the amount you win equals or exceeds the amount you have staked on that spin. A game with a low hit rate on the other hand can pay out more when you land on a winning combination. Of course, ideally you should look for slots with a decent hit rate and but which offers high payouts too!

Slot volatility, or slot variance, refers to how frequently the slot pays out, as well as how much. Slots of low volatility typically have a high hit rate, but reward players with smaller payouts on each win. On the other hand, slots with high volatility reward you with big payouts much less frequently, and normally the biggest prizes will be won following a bonus game or after landing on a (hard-to-get) combination of the highest paying symbol. Players on a budget should seek to make smaller stakes on high volatility slots so they could play longer and get a chance of triggering the bonus or landing on a big win. In slots of medium volatility, you’ll find a more balanced combination of small, medium and large wins.

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How can slot volatility help you choose which slots to play?

Essentially, slot volatility all comes down to player preferences. 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 or win a hefty sum. 

Slot RTP

Known as Return to Player, RTP is a percentage that a slot pays back after a theoretical number of spins. Online slots typically have an RTP of between 95 and 98%, with the average being around 96%. An RTP of 96% would mean that over millions of rounds, you can expect the slot to pay out £96 back for every £100 staked. However, we all know that more often than not this is not the case. You may still end up spinning 10 times and not winning anything at all (in which case the RTP would be 0%), whereas one day you might start playing and hit a jackpot on the first spin (this is the RNG at work). If you really get paid back £96 for every £100 you stake, then the slot would be of zero variance.

Slot RTP is only one of the factors to consider when choosing a slot but should only serve as an indication of how much the game is expected to pay out. Low volatility slots typically have a rather high RTP but may not yield the big win you may be after. This is why a lot of gamblers, especially high rollers, prefer to play medium to high variance slots (even if the RTP is slightly lower), since they are playing in the hope of securing those big payouts. 

You can find a list of slots with high RTP here!

Analyse RTP, volatility and slot hit rate with Slot Tracker

Slot Tracker can help you compare RTP percentages, slot hit rate, bonus frequency and volatility thanks to its in-depth data. This will help you understand how individual slots work, so that you could choose the best ones to play for real money. Get informed so that you can play for longer and win more on slots with the help of this tool, and best of luck!

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