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Slots

How a slot machine decides an outcome, what payback percentages mean on a state report, and where the myths about hot and cold machines come from.

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Old slot machines set out for scrapping
Photo: Agência Brasil · CC BY 3.0 br · Wikimedia Commons

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About this section

Whether you love religiously playing online slots or enjoy a monthly outing to the local casino, slots hold a special place in any gambler's heart.

How To Play Slots

Whether you want to play slot machines in a land-based casino or play online slots, the course of action remains the same.

1. Select a slot machine

To play slots, you must decide what types of slot machines match your risk appetite, bankroll, and personal preferences. Concepts that matter a lot here are:

Some slot games have a high variance, meaning they pay big but rarely. Others do the exact opposite. Additionally, playing slots is mostly about having fun responsibly, so you should also pick a slot theme that is exciting to you. All information, including the RTP, is usually displayed on the cabinet or within the game. Some players can engage with their game for hours, so don't pick something boring!

2. Add some credit

Once a slot game is picked, it is time to add credits. In a real casino, credits are either tickets that represent cash that you insert in the machine, cash, or casino chips. Online, that's generally based on your staked bankroll.

3. Master the gameplay

Casino game developers have come a long way since the days of the classical slot machines with a single payline. Nowadays, video slots can have dozens of paylines, straight and zig-zag winning combinations, as well as bonus symbols, and free spins. Oh, and did I forget the simple jackpots, progressive jackpots, and a last one, wide-area progressive jackpots.

Learning the paytable might actually be impossible so try to get a good grasp of the key features. Finally, make sure you bet whatever amounts are required if you are chasing a specific jackpot or bonus feature (generally the "bet max").

Types of Slots

Our list of the most common types of slots.

  • Multi-line slots
  • 5-Reel slots
  • All-Ways slots
  • Progressive slots
  • Mobile slots
  • Basic slots
  • Fruit slots
  • 3D video slots
  • Amusement-with-prize slots
  • Five-liner slots
  • Three-liner slots
  • Five-liner slots
  • Onesies slots
  • Penny slots
  • Tumbling-reels slots
  • Wide-area progressive slots

Casino game developers create new gameplays and enticing new features regularly. Always be on the lookout for the latest trends and new slots!

How To Pick Slots

If you spent some time with gamblers, you will hear that most of them go with their intuition when picking slots to play. "The machine was hot", or "avoid this online slot machine, it's a cold one". Let's kill the myth now - slots aren't cold or hot! Instead, they have features and metrics to help you choose the one(s) right for you and know which are the best online slots for your money. Some of this data is public - though not entirely!

RTP

The return-to-player rate, or RTP, is a percentage-based measure of how much of all money entered in a machine will be paid out to players. Generally, slots RTP are around 90 to 95 percent. The missing chunk is the house edge (what casinos keep).

Many casino game software developers make this information public, and so do some land-based casinos. The worry with making this information widely available is that it would essentially get players to only play on the one slot that offers the highest RTP. This is why software providers such as Microgaming find other ways to market their games such as having a TV show or movie theme. There are even the likes of Betsoft that market their slots as a 3D movie experience.

To summarize, a slot game with a high RTP (above 95%) will return a lot of the received wagers back to players over time. Lower RTP games don't return as much whilst medium-RTP slots sit in between.

House Edge

An online or land-based casino slot machine gets money and returns a predetermined percentage of it called the return-to-player rate. Everything else is the house edge and is kept by the casino. A casino's house edge is also referred to as its holding rate or holding percentage. Real-money online slots are set to make money for the operator.

For example, a video slot machine with an RTP of 93.5% has a house edge of 6.5%. An online slot game with an RTP of 96.75% has a holding rate of 3.25%.

Variance

Slot variance, or slot volatility, is defined as the likelihood of hitting a winning combination.

Therefore, high-variance slots rarely land winning combinations on the reels but have therefore bigger payouts. Inversely, low-variance slots have frequent wins but consequently, payouts are smaller. Medium-variance slots hit a sweet spot for occasional gamblers.

The volatility of slot machines is important for players to consider. For instance, if your bankroll is quite low, you would naturally prefer a low-variance slot machine in order to keep on playing. High-variance slots may go for long stretches without giving any winning combo - they are high risk and high reward!

Features

Not everything is about mathematics in slots. Features is an umbrella term to talk about the characteristics of a slot machine. Features mostly revolve around the specific gameplay for that video slot which translates into its slot symbols and icons, its number of reels and rows, as well as its paytable and paylines.

Bonus symbols, wilds, scatters, multipliers, free spin symbols, and more. Features make playing slots different between games. Whilst you do want an exciting game whilst spinning reels, things get very confusing nowadays as slot machine developers craft very absorbing and mesmerizing features. When talking to slot fanciers, we discovered that most of them barely understand paytables these days. They simply spin and hope that the screen lights up with a patchwork of wins!

Themes

When wondering how to choose a slot machine, online or offline, the game's theme should come into play. From seasonal slots to classical slots, different people love different slot themes. Huge hollywood franchises have their own branded slot games.

Here, there are no objective guidelines. It is mostly about what you enjoy sitting down in front of and staring at for hours of play.

Online Slots vs Real Slots

Nowadays, there are virtually no differences between online slots and real land-based casino slots. Both are computerized and have no mechanical parts. Therefore, the software running online and real slots are very similar, if not identical in most instances.

The only differentiating point is how the game is controlled. Whilst you have your touchscreen and mouse at home, you will have the big buttons and touchscreen controls in the casino.

Overall, both experiences are bound to be merging as the slot games themselves are simply pieces of software. Very exciting and fun software, though.

Slots FAQ

Understandably, we aren't born with a slot machine strategy ready to be used. So we have gathered the most frequently asked questions about casino slots, both online and land-based, and answered them concisely.

Which slot machines pay the best?

Based on their return-to-player rates, some of the online slots with the highest payouts are Ugga Bugga by Playtech (RTP 99.07%), Mega Joker by NetEnt (RTP 99%), and Ooh Aah Dracula by Barcrest (RTP 99%).

Are online slots rigged?

Online slots are not rigged. The estimated payout rate for each slot is often known publicly. Additionally, casinos are not allowed to make false or inflated claims. The business model for slots is one of volume, and casinos are happy with taking a very small percentage (around 5%) of all slots money while paying out the rest (around 95%) to the players.

Where to find free vegas slots?

Free vegas slots are available on most online casino sites with freerolls or low-stake bets. They are the most popular and classical type of slots. Indeed, free vegas slots are generally a gateway for casinos to entice newcomers as they are easily understandable and playable.

Are penny slots worth it?

Penny slots are a low-risk low-reward type of slot machine. Both online and offline penny slot machines may not pay the largest sums but they do allow for long sessions loved by everybody. High rollers and VIPs should obviously avoid penny slots like the plague.

How to find online slots RTP?

Most slot game developers provide a technical brochure describing their machines along with specifications such as the RTP rate. These help casino executives then decide whether they want to offer such slots in their casino offering or not.

Our website also reviews a large number of online video slots and provides the RTP alongside useful information.

How to cheat at online slots?

The not-so-honest ways of cheating at online slots include bonus hunting, account cloning, and no-deposit bonus chasing. And so, it is somewhat impossible to just cheat the pseudorandom number generator that powers nearly all online video slots.

How to win at real casino slots?

Whilst there is no sure way of winning at slots, the best slot strategy to win at real slots is to choose higher denomination slots, bet enough to unlock special features and large jackpots, and don't play on multiple slot machines at the same time.

Are casino slot machines honest?

Casino slot machines are honest and often independently checked to ensure the random number generation is fair. Additionally, casinos never make false claims as they would risk huge fines and sanctions. Casinos make money through the house edge, holding a small percentage of all the money played in each slot.

How to win on penny slot machines?

Penny slots are generally low-variance slots which naturally pay often but very small amounts. Therefore, it is quite easy to win at penny slots by simply playing enough time. However, you will not win big as such slots are engineered for low-risk personalities.

What is a random number generator (RNP) in slots?

In slots and other computerized platforms, a random number generator is a program that generates a sequence of numbers that can't be predicted other than by chance. Many slots use a pseudorandom number generator instead, which doesn't really require any physical or mechanical random seed.