One-armed bandit, fruit machine, pokies, pokey – whatever you call them, slot machines remain the most popular casino game for years. They are so popular that 70% of all revenues for an average casino in the United States are thought to come from slot games. Thanks to online casinos, you no longer have to leave your home to play them: you can play online slots anytime from your computer or mobile phone. But before you do that, you need to know as much as possible about online slot machines. Thus, you can have more fun and maximise your winning potential. That's exactly what we're going to do in this guide: below, we talk about everything you need to know about casino slot machines and let you start playing the best online slots today.
The first thing you need to know is that not all casino slots online are the same. At first glance, you might think they all look alike, and to a certain extent, this is true: the main purpose of these games is always the same. However, they are quite different from each other in terms of gameplay, features, and payout potential. Below we list the main types of online slots and explain what to expect from each.
These are also known as "fruit machines" and are the closest games to the original design of slot machines. They can also be called “Vegas slots” based on the theme they use. In any case, the numbers of their reels and paylines are limited. They usually have 3 reels and 5 paylines, but the number of lines can be less or slightly higher (9 maximum). Classic online slots mostly do not have special symbols and bonus features. All you have to do is place identical symbols next to each other.
These types of games almost always fall into the "low volatility" category, so you win often, but the payout is low. You can start playing in a few minutes as there are no special rules you need to learn. Classic slots are a good option for beginners or those on a limited budget as they are simple, and the betting ranges are low enough to appeal to low budgets.
You can think of them as upgraded versions of classic slots. The graphics and animation quality are much better, but that's not the only difference. Video slots have 10 paylines with at least 5 reels. Themes in these games are diverse, including pirate-themed slots, and cover topics like aliens and Ancient Egypt. They have special symbols (e.g., wild–scatter) and bonus features (e.g., free spins). In this respect, their gameplay offers more than classic slots because you have more options to win.
Although they have slightly more complex gameplay compared to the classic slots, they are still suitable for beginners. You just have to pay attention to the factors that trigger the bonus features. In some special variants, the number of reels can reach seven, and the number of lines can exceed a thousand. There may even be 117,649 lines in video slots like "Megaways". They have a wide variety of betting ranges, so they are suitable for players of all experience levels and for any budget.
These are actually video slots, but their graphics and animation quality are very high. In some games, the graphics quality can compete with CGI movies. 3D slots are often adapted from movies, but there are also studios that develop their own original titles. They are no different from video slots except for their visual quality, but sometimes they can also offer creative mini-games instead of bonus features like free spins. Below you can see some of the best online slots of this type:
These games can be classic or video slots according to their features. But whichever they are, they always have a big prize (jackpot) to be won. In other words, in addition to the symbol and feature payouts, there is one more big payout you can win. The amount of this reward is fixed and does not change. What you need to do to win the jackpot is different in every game, but you usually have to land five specific symbols next to each other. Below you can see some of the top online slots in the fixed jackpot category:
The difference between jackpot games and these is that the big prize is not fixed. In progressive jackpots, the jackpot amount continues to increase with each game played and lost. This situation continues until a player wins, and the jackpot can sometimes reach millions for the same reason. Progressive jackpots can make you a millionaire with a single spin. However, as we'll point out below, these games have low RTP, meaning it takes longer to win than it normally would:
Whatever type of online slot machines you prefer, the main goal is always the same: placing identical symbols next to each other. Depending on the number and type of symbols you place, you are entitled to different payouts. Usually, at least three symbols are required to qualify for a payout, but in some slot games, it can be two as well. Each set of symbols has a different payout value: some sets pay high, and some pay low. You can check the game's paytable to learn about the symbol sets and their payout values.
Although that should always be your main goal, some casino slot machines also offer different options to qualify for a payout. For example, a video slot can increase the payout when you land a symbol set with a wild symbol in it. Likewise, you can trigger a bonus feature (for example, free spins) by placing scatter symbols. As we mentioned above, it is also possible to win the jackpot with a special set of symbols too.
The best thing you can do in this regard is again to take a look at the game's paytable: there are no fixed rules that apply to all online slots. These are general information, and you should always check the paytable before you start to play slots online to find out all you can do to qualify for a payout.
In any case, symbol sets are the key to getting a payout or triggering a bonus feature. These symbols must land on paylines (also known as “betlines” or “winlines”). These are real lines that connect both ends of the reels. In some online slots, you can see for a few seconds what they look like after qualifying for a payout: they are sometimes straight, sometimes zigzag lines, and run from the first reel to the last reel. In other words, what you need to understand by “placing them next to each other” is not just a straight line: symbols in different positions can also turn into a winning combination, as long as they are on a payline.
RNG Guarantees Random Results
What makes casino slots online special is that the spin results are always randomly determined. Because of that, it is not possible to define a system or strategy that will increase your chances of winning, as is the case with games such as blackjack and roulette. For the same reason, there is no difference between a professional gambler and a beginner: both have the same chance of winning when they play slot machines online. You can't challenge a professional gambler in poker, but there is no difference between your chances to win real money in desktop and mobile slots.
What makes this possible is the RNG (random number generator) software. The sole purpose of this software is to generate random numbers. Every symbol in casino slot machines has a numerical equivalent, and when the numbers generated by RNG match them, this determines which symbols will be displayed on the screen. This is why the results are random: since it is not possible to predict the RNG results, it is also not possible to predict what will happen in the next spin.
Online Slots Terminology
Normally, you have to click the button of the same name to make a spin. This feature allows a certain number of automatic spins (for example, 100 times).
The maximum bet you can place for that spin.
Bet per Line
The amount of bet placed per line. It determines what the bet per spin will be. For example, if we bet 0.10 EUR/USD per line and the game has 20 lines, the actual bet is 2 EUR/USD per spin (0.10 x 20).
Symbol sets are calculated from left to right to determine whether you win or not. If this feature is active, both ways (left to right – right to left) are taken into account.
This means that the bonus feature of the slot can be purchased directly. For example, you do not need to use scatter symbols to trigger free spins, you can start them immediately by paying.
After a winning combination is formed, all symbols in that combination disappear, and new symbols appear without the need for a new spin. In this way, it is possible to trigger another win.
This is the name of a bonus feature. It is usually triggered by a certain number of scatter symbols and entitles the player to make a certain number of spins (for example, 20) for free. If you win real money with these spins, it's yours.
It is a mini-game where you try to guess the colour or suit of play cards. It can be activated manually after a winning spin. If you win, you can double or even quadruple the payout.
Means “to win”. Every spin that results in a win is a “hit”.
It is the name given to online slots that pay out frequently and in high amounts.
Indicates that there is more than one payline in that game.
In some online slot machines, payouts for symbols and features are not a fixed value, but rather a bet multiplier. For example, if the "star" symbol pays 5x, the actual payout value is determined by multiplying the stake by 5.
Also known as RTP. It shows how much of your investment in online slots can be recovered in the long run. For example, if you invest 100 EUR/USD on a slot with a payout percentage of 98%, you will win back 98 EUR/USD in the long run.
When a certain condition is met (for example, two wild symbols appear), reels spin once more, automatically and for free.
A special symbol that can pay without having to place it on a payline. It is also mostly used to trigger a bonus feature (e.g., free spins).
It is the name given to wild symbols that are placed on top of each other on the same reel.
A term used for online slots with a low payout frequency.
It is a special symbol that can substitute for other symbols. For example, if three symbols are required to win a payout, you can also complete this combination with two symbols + one wild symbol.
Also known as "variance". It determines how often and how large the online slot machines pay out. High volatility games rarely pay but in big amounts. Low volatility games, on the other hand, pay often but in low amounts.
Choosing the Right Slot Game
First of all, choose online slots that will allow you to use your budget most efficiently
Your main goal in these games should be to extend the game time (and the number of spins) as much as possible. The more spins you make, the more chances you get to win real money. Therefore, the first thing you should consider must be the betting range: choose online slot machines whose minimum and maximum bets fit your budget best. Those who play on a limited budget may prefer “penny slots”: in these games, you can spin with just one penny.
Choose casino slots online that use a theme you love
These games have dozens of different themes, and you can find hundreds of options for each. You can get more fun and enjoyable experience in games with a theme you like.
Be sure to test online slots on mobile devices as well
As we'll explain below, modern online slots can run smoothly on all platforms but it would be best to make sure. iOS or Android, whichever you are using, play the game on that device and see if there are any problems.
You don't just have to choose between new and popular online slot machines
Even games released 10 years ago can still provide you with an enjoyable and satisfying experience. For example, Cleopatra, developed by IGT, is one of the oldest video slots on the market, but still offers incredible winning potential.
Whatever game you choose, be sure to try the free (demo) version first
All online slot machines have a free-to-play version. They are no different in terms of winning chances, rules, and payouts. They don't just pay with real money (and don't accept real bets). By playing the demo versions, you can choose the best online slots for you without risk and play only the games of your choice for real. In the table below you can see the differences between free slots and slots with real money.
You can play for free
The payouts are not real
You don’t take any risk
Online casinos are not the only place you can play them: free slots can be found at other sites too
You can’t use gambling bonuses
SLOTS WITH REAL MONEY
You must place a real money bet
The payouts are real
There is always a risk of losing money
You can play for real only at online casinos
You can use gambling bonuses
Slot Games Casino Bonuses
Online casinos have many promotions and both new and existing members can benefit from them. Due to their popularity, casino slot machines are included in almost every promotion. In other words, when you join an online casino for the first time and afterwards, you can enjoy many bonuses that can be used to play slots online. It is possible to divide these bonuses into two basic categories.
Bonuses with Free Spins
“Free spin” is a feature only available in online slot machines. You can spin the reels a certain number of times without paying for them and if you win real money, you are allowed to keep it. In this bonus, the casino offers exactly that. In other words, it awards a certain number of free spins that you can use on a particular slot (or multiple slot machines).
You can claim this bonus by performing a certain action. This is usually depositing a certain amount. For example, for a deposit of 20 EUR/USD, the casino gives you 50 free spins that you can use on a popular slot. Sometimes it is possible to get a small number of free spins just by becoming a member (without making a deposit), this is called a “no deposit free spin” bonus. This promotion can be stand-alone or included in another promotion (for example, in a welcome pack).
Bonuses Giving a Cash Balance
This promotion gives you a bonus cash balance. Your deposit is matched by the casino at a certain rate: for example, when you deposit 10 EUR/USD, the casino will match it 100%, adding another 10 EUR/USD to your account. Since this is an actual balance, it is possible to use it on slot machines too. So, you can also play slots with real money, and you can use your bonus balance for the bet you need to place.
This is not an ideal solution, just an option. Ideally, you should use the free spins bonuses to play slot machines online and the cash bonuses for other games. But this is not a mandatory thing: if you really like to play casino slots online, you can use your cash bonus for that purpose too.
Whichever of the above bonuses you use, you will be asked to complete wagering requirements. Simply put, players in a casino have two balances, "real" and "bonus". The deposits you make are transferred to your real balance and can be used to play for real (for example, playing slots with real money). Your bonuses and the winnings you make using them are transferred to your bonus balance. So, the amount you win with your free spins (or no deposit free spin) bonus will be credited to your bonus balance, not real.
The bonus balance is always locked, and a certain amount of money must be wagered in order to unlock it. This is what is meant by the wagering requirement: wagering means using the money in your real balance to play games. The amount of money you must wager is determined by the casino and is shown in the bonus conditions (as the wagering rate). You can simply use this formula:
Amount in bonus balance x wagering rate = money you have to wager
For example, let's say you use your free spin bonus to play top online slots and win 50 EUR/USD. Let the wagering rate be 25x. In this case, the formula would be:
50 x 25 = 1,250
So, in order to use (or withdraw) your bonus balance of 50 EUR/USD, you will first need to wager 1,250 EUR/USD. Predictably, the lower the wagering rate, the better. Below, in the strategies section, we'll also talk about other things to watch out for in this regard.
Choosing the Best Casino to Play Slots Online
If you want to play top online slots, you should choose the best casinos. Every online casino claims to be the best, so in order to play at really good casinos, you have to pay attention to some things. Below we explain how to choose casinos where you can find the best online slots.
Start with the license check
If you want a smooth, legal, safe, and fair experience, you should only choose licensed online casinos (usually, the license can be found at the bottom of the page). That should be your first criterion: do not play at an unlicensed casino.
Check out the slots collection
Make sure that the online slot machines are satisfactory both in quality and in number. The game collection should be provided by the respected and well-established developers of the iGaming industry. You should be able to play all the slot types we listed above and find hundreds of options in each.
Make sure that there are bonuses that you can use both as a new member and afterward on popular and top online slots. In other words, the casino should be offering a large number of free spin bonuses and these bonuses should have fair terms.
Try it on mobile devices
Try both games and other services (for example, payments) on mobile to make sure you can have a smooth experience on mobile as well. Make sure you can play mobile slots on all your devices without any problems.
Best verified casinos
Number of slot games:1500 slot gamesFree spins:
As we mentioned above, it is not possible to develop a system or strategy that you can use to play slot machines online and win real money due to random results. However, by paying attention to some things, it is possible to increase the frequency of winning and losing as little as possible.
Prefer games with a high RTP percentage
We explained above what RTP is: the higher this ratio, the less you lose. As a general rule, choose online slot machines with an RTP of at least 95%. You can find the RTP of a game in the paytable.
Stay away from progressive jackpots unless you have a big budget
The RTP of these games ranges from 80% to 90%, which is normal due to the size of the prize amount. However, this also means that you have to spin more than usual to win. If you don't have a big budget, this will be a problem.
Always try to play fixed jackpot games with the maximum bet
These games trigger the jackpot more often when played with the max bet: don't play with a minimum bet and expect to win.
You can still play a game over your budget by reducing the number of lines
Doing so will also reduce the min/max bet limits. But keep in mind that as the number of lines decreases, the probability of winning combinations decreases too.
Mobile Slots Online
Nowadays, you do not need to choose a particular studio or website to find casino slots online that also work on mobile devices. It is possible to say that all online slots developed in 2010 and later will work smoothly on mobile devices. This is because developers have completely migrated to HTML5 technology in the last 10 years. Casino slot machines using this technology run directly on web browsers. Therefore, the operating system does not matter, and no download is required. Simply select the game and tap the play button: your chosen slot will be launched in a few seconds. Currently, a very large part of the games on the market are considered native mobile slots and can be played in this way.
Games developed before 2010 can also be played on mobile devices, but you need to be careful on which platform they are developed. In those years, studios were also developing games with the Flash platform. This platform has become obsolete nowadays, but the online slots developed with it are still available in the market. Flash-based mobile slots can only work on Android devices. They cannot work on iOS devices due to the OS not supporting them: you have to use a separate app.
Fortunately, this type of mobile slots are very few in number and you have to make an almost special effort to find them. Currently, you can play more than 90% of slot machines in online casinos on any mobile device without any problems and no download will be needed.
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Will is responsible for English content. Will prepares slot and casino reviews regularly and knows all mainstreams of modern iGaming. Being a talented and diligent writer, he could cope with practically any task. He could fastly switch between different subjects and provide content of the highest quality. Will is an expert with analysis and research, that’s why we are always sure he will produce unbiased content.
FAQ About Online Slot Machines
What are slots special symbols?
In slot games, some symbols only pay, while others also activate some functions (for example, the free spins round). Symbols with such additional properties are called “special symbols”. The most common examples are wilds and scatters, but all slots can also have their own unique symbols. By looking at the game's paytable, you can see all the special symbols and what they do.
What slots are better, high-volatility or low?
High volatility means that the payout frequency will be low, but the payout amount will be high. Low volatility, on the other hand, indicates that payouts will be made frequently, but the payout amount will be low. Which of these is better is a personal choice. If you have a limited budget, low volatility slots may be a better choice because you start winning earlier. If you don't have a budget problem, high volatility slots may be more satisfying.
What are slots with a progressive jackpot?
There is a big prize that can be won in progressive jackpots, and the amount of it keeps increasing with every game played (that's why it's called progressive). The figure accumulated in the prize pool grows with each game played and lost, and sometimes it can reach millions. This number keeps increasing until someone wins.
Is an online slot game totally random?
Yes, because an RNG software (random number generator) determines what the spin result will be. Every symbol in the slots has a numerical equivalent. RNG generates a random number and if this number corresponds to one of the symbols, that symbol is displayed on the screen. It is not possible to know in advance what this number (and therefore the symbol to be displayed) will be.