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How do slot machines work? Is the activity a game of chance, or is there a secret sauce that you can use to win? Slot machines are the most played casino game online and in the live casino. However, you need to know how slot machine lines work before you head off to your nearest casino. Our guide will show you how slots work and how you can get the most out of your play.
(Source: Pexels / Darya Sannikova)
How to Play Slot Machines
The lure of online slot games is undeniable: you spin the reels and watch eye-catching graphics as the paylines match up. You can play slots online or in person at land-based casinos. Before we look at how slots work in traditional casinos, let’s investigate how you can get started.
Online Slots
Online casino slots come in all shapes and sizes with different bonus symbols and a number of paylines in each game. The online slot games you find nowadays have various themes and special features. But for all the different titles you will find online, the basic idea behind them is still the same.
So, how do online slots work? Random number generators govern the software. Online slots use RNGs to produce large sets of random numbers. These numbers determine what symbols appear where on each of the reels.
To start playing online slots, select the amount you set on each round and click the spin button – and that’s it. If you are not ready to play for real, you can also try the games in demo mode.
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Land-Based Slot Machines
How do slot machines work in land-based casinos? Traditional slots use the same randomness principle. RNGs also dictate outcomes in these games.
However, you will have a choice of two options – mechanical or video slots. Mechanical slots are traditional machines with physical reels that sometimes use microchips to determine outcomes. To get started on mechanical slots, there is a lever that you must pull on to activate the reels.
Video slots operate differently from how slots work in traditional casinos. They use microchips for random number generation, game logic, payouts, and machine communication. Microchips and other advanced components have replaced physical reels with large screen displays in these games. To play video slots, you just hit the spin button and wait for the reels to stop randomly.
Payouts and Odds
How do slot machines pay out? When figuring out how slot machines work, you need to understand that every game has a paytable. You can find this paytable in the game’s information sheet, which spells out how much you win for each combination of symbols. Match cherries? Get 100 coins. Line up three main characters? Ten free spins.
Slot machine payouts are programmed, ensuring the casino has a predictable house edge. So it begs the question, are slot machines rigged? No way! You can learn more about how slot machines are programmed in our “How to play slot machines” guide.
Understanding the House Edge
Winning slot machines is about luck, but there is also an invisible hand called the Return to Player (RTP) percentage that impacts long-term payouts. Take a 96% RTP, for example. It means the house will keep 4% of all wagers and return the more significant portion of 96%. Ultimately, the house will always have an edge on every spin.
RTP is a long-term average, and you could win big in a couple of lucky spins. But in the end, the math will always balance out. The house will have an advantage over the service life of the slot. So, the key is to play responsibly.
Why are RTPs on Land-Based Slot Machines Different From Online Slots?
Generally, online casino slots offer better RTPs compared to traditional slot machines. There are various reasons for this anomaly, and we will discuss some of them here.
First, land-based casinos have huge overheads. The cost of acquiring physical space, staff, and machine maintenance means there is little left over for competitive RTPs. At online casinos, on the other hand, slots operate virtually. This means they can offer higher RTPs, sometimes even reaching 99%.
Another reason we see the difference in levels of RTPs in online and land-based slots is competition. Land-based casinos are heavily regulated, and you need to jump through a few hoops before establishing a physical operation.
This larger barrier to entry means there is less competition to attract players. Virtual casinos compete in a saturated market, which affects how online slots work. A site must have a competitive advantage: offering higher RTPs is one way.
RTP of Slot Machines Compared to Other Games
When understanding slot machines RTP, you must realize it’s never a size-fits-all. As established, land-based casino slots have different RTPs than online slots. Likewise, you will find varying RTPs across different casino game types.
The table below shows the theoretical RTP ranges of various casino games.
| Game | Theoretical RTP% |
|---|---|
| Slot machine (land-based) | 85-93% |
| Online slot | 91-99% |
| Roulette | 94.74-97.3% |
| Blackjack (Basic Strategy) | 99.4-99.6% |
| Craps (Pass Line Bet) | 96.58-98.56% |
| Video Poker (Optimal Play) | 95-99.9% |
Different Types of Slot Machines
Your slot gaming experience can vary depending on where you play in the US. Some states have caps on maximum payouts, meaning there is a limit to the amount of money you can win.
It’s important to realize that US slot machine games fall into two main categories: Class II and Class III. Class II slot machines have a bingo-based technology instead of random number generators. These games are mainly found in tribal casinos, and as such, jackpots are limited due to federal regulations and individual agreements.
Class III physical slot machines are available at commercial casinos and are closer to online video slots. Jackpot wins are usually uncapped, but this might not be the case in some instances. Therefore, you must check with the regulations to establish if there is a limit on how much you can win.
Mechanical Slots
In the most basic sense, a slot machine is just a game of chance. Here, players place wagers on the likelihood of symbols populating a winning payline. The paylines in mechanical slots spread across physical reels that spin and stop independently. These games have tangible levers, spring mechanisms, and unique sounds that enhance the gameplay.
Video Slots
Video slots differ from mechanical slots because they don’t have physical reels but rather large screen displays with stunning high-definition visuals. The mode of operation is also different: video slots don’t have mechanical spring-loaded levers – you only have to press a button when you want to start the game. In addition, these games have multiple paylines and winning combinations.
Online Slots
So far, both slot types we have discussed are available in land-based casinos. But there is a third type that you can play anywhere, even from the comfort of your home. You can play online slots on a PC, tablet, or smartphone. This software runs on web and native applications compatible with Android, iOS, and other mobile casino platforms.
There is no comparison between traditional Las Vegas and online slots because these products appeal to a different market. If you like the lively casino atmosphere, with all the loud machines, and don’t mind traveling, traditional mechanical slots are the way to go. But if you prefer the convenience of playing where and when you want, online slots are it.
What is a Random Number Generator?
Regarding how slots work, all slot machines use Random Number Generators (RNGs) to establish randomness. RNGs are complex instructions to produce an unending supply of random numbers. When you take a spin on a slot machine, a unique number is assigned to each reel. And this number determines where the reel will rest and where the winning numbers are.
Each spin you take is considered an independent event. The previous spin and its outcome must not have any bearing or influence on the number of symbols that match on a win line. That’s where random number generators come into play.
RNGs control the game’s behavior, so manipulating these instructions will lead to false outcomes. That’s why third-party fairness checkers audit slot machine games regularly to prove they haven’t been tampered with.
Many organizations provide this checking service for online casinos. Companies like eCogra and Gaming Labs International are among the most reputable. A seal from either of these organizations guarantees that you don’t need to worry if the slots are random or not when you play.
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How Do Progressive Slot Machines Work?
Progressive slots are a step away from traditional slot machines. Unlike standard reel games with fixed jackpots, progressive jackpots grow with each wager placed on a game. This means the most significant wins on slot machines will come from progressive jackpot games.
How do progressive slot machines work? A small percentage is taken away from each spin made on a slot machine game. This amount can be a fixed portion of each wager or a percentage. The more popular a progressive slot machine is, the quicker the jackpot grows.
You trigger a jackpot by hitting special symbols. Alternatively, you may activate a bonus game by landing scatter symbols on the reels.
Progressive slot machines can be classified as ‘local area’ or ‘wide area’. Local progressive jackpots are available in a single casino, and the jackpot is linked to slots found in that location. Naturally, potential payouts in these games are relatively smaller, but you will have higher chances of winning.
In the United States, wide-area jackpots cover multiple casinos and states. More players are adding to the pot, meaning the jackpots can rise to staggering levels quickly. Similarly, online progressive slot jackpots are available across multiple jurisdictions and sometimes even several countries.
Final Thoughts
This How Slots Work guide has revealed that slot machines provide an easy and exciting route to casino gaming. Many options are available at in-person casinos across the US. Whether you are looking for traditional slots or more advanced video alternatives, you will find a game that suits you.
But these games, easy as they may be, come with a pre-programmed house edge. The return to player percentage can reveal how a slot machine pays out. But being a long-term average, RTP doesn’t help you understand whether you will win.
The best casino slots offer progressive jackpots. These jackpots vary in size but are most significant at online sites. You can check out online progressive jackpot slots today at your favorite casino without leaving the comfort of your home.
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How Do Slot Machines Work? FAQs
How do casino slot machines work?
How much can I win on slots?
Are slot machines rigged?
Are slot machines actually random?
Responsible Gambling
We encourage you to gamble responsibly when learning how to play slots and other games of chance. Never gamble with money you are not willing to lose. If your gambling is affecting you and those around you, seek help early. More details are available on our responsible gambling page.
Resources
Other helpful resources to learn about how slots pay out and more are available here:
