Slot machines are the most popular games at any online casino. The machines come in many different versions, including regular slots, video slots and jackpot slots to name a few. The best slot machines are those that combine great graphics with exciting bonus rounds, unique extra features and the potential for huge wins.
The machines come in thousands of variants, with different designs, bonus features, number of pay lines, and payout sizes. But they have one thing in common: the goal of spinning the reels is to get matching symbols in the right places. And since this happens automatically, it does not require a lot of personal effort to familiarize yourself with the rules and understand what is happening.
Slots is simply the ultimate casino game for beginners who have never played at a casino before. We believe this is why slot machines are as popular as they are: You do not need any prior knowledge to win.
Best casinos to play slot machine games
For those of you who are looking for a wide selection of slot machines, we can recommend the casinos from the lists below.
Wondering which slot machine to choose? We have tested hundreds of slot machines for you! Check out our slot reviews and find something you like!
Rules – No two games are alike
Different slot machines often have slightly different rules. They really have a lot in common, in that they are all about betting an amount, spinning the wheels and hoping for matching symbols. But the details can vary from game to game.
For example, you will find large variations in how large (and small) amounts you can bet, how big the winnings can be and how many paylines you can play with, to name a few.
In some games, you increase in “skill level” while playing, while the winnings get bigger and bigger. In others, there is a fixed jackpot that applies. Sometimes you will be able to double the winnings in traditional get rid of or double style, and in the progressive jackpots, the winnings have no end.
To know what applies, you simply need to check the rules of the game. All slot machines have a small “i” icon where you can find more information. There you will be explained, for example, how much each of the symbols is worth, where they must land for you to win, and how bonus features and free spins work. The information is often given in English, but well-known developers such as NetEnt, Microgaming and several others provide the information in other popular languages as well. As we mentioned earlier, we have plenty of our slot machine reviews where we explain how the game works and what we think after testing.
You can also change settings on the games. For example, you can change the bet level (how much money you bet on each spin), turn on autoplay (the machine spins by itself a given number of times) and adjust sound effects.
Basic rules that apply to most slot machines
Below we take a look at general rules that are common to most slot machines. If you understand these rules, you will quickly understand most of the slot machines out there, without too much trouble.
Symbols and symbol value
Most slot machines today contain several symbols. Preferably 8-10, and maybe even more. The symbols have different values and give different payouts on the winnings. The same payline can thus give two completely different wins, depending on which symbols it consists of, as well as how many identical symbols stand in a row. To get an overview of which symbols are worth what, you can go into the game rules and find the overview there. In the picture below we see, for example, that the “BAR” symbol gives a win of 250 coins if you get 5 symbols in a row. How much this equates to in money depends on the coin value you choose to play with. More about this further down.
Paylines 
A slot machine often has a number of different paylines. A regular payline is a line of identical symbols running from left to right on the screen. In addition, developers are happy to add more paylines. These can zigzag or shape different patterns on the screen, as shown in the section below from the Starburst video slot machine. The more paylines you bet on, the more chances of winning you have. But it will also cost you more, as the bet per spin is multiplied by the number of paylines you choose to bet on.
Also note that the number of paylines may vary from game to game. The simplest slot machines may have only 5 lines (then you can often not choose how many you want to bet on), while others have several hundred. There are also some slot machines where you have to play with all the paylines active. But in these games, you can almost always choose a low coin value if desired.
On most slot machines, the paylines are read from left to right, but some slot machines break this formula. For example, Starburst reads the paylines from both sides which means that 3 identical symbols to the right of a payline will also pay out.
It is also worth noting that you can win on several paylines at once. This often leads to multiplier wins where you can win even more than if the wins came individually.
Stake level
The bet level says something about how many paylines you bet per spin, as well as the number of coins bet. Level 1 is the default level. Then bet exactly the amount you have chosen, and a predetermined number of coins. At level two, the number of coins doubles, and you play on an increased number of paylines. At the level, the number of coins triples, and so on.
In a game like Starburst, where there are a total of 10 paylines, each bet level corresponds to a bet on one additional payline, as well as an increase in bet of 10 coins. While on a slot machine with, for example, 100 paylines, it can be the case that each bet level increases the number of paylines you play on by 10 pieces.
In order to be absolutely sure that you are playing correctly and that you actually understand the game, we recommend that you take a look at the information about the game before you start. And possibly play with play money before you start playing with your own money.
Coin value and number of coins
Slot machines usually operate with so-called coin value. The coin value says something about how much money you want to bet per digital “coin” you put on the machine. These are often stated in euros, but sometimes you can also play with other currencies (CAD, USD, NZD, GBP, etc). A typical coin value can range from 0.10 – 1.00 euros. But keep in mind that you are not necessarily betting just one coin per spin. How many coins are bet is often determined when choosing the bet level.
On the Starburst video slot, you can bet a minimum of 10 coins, and each increase in bet level will increase the number of coins by 10. Thus, you can bet a total of 100 coins per spin if you play at bet level 10.
Example of cost for one spin at maximum coin value and maximum bet level on Starburst:
- Coin value: 1 euro
- Stake level: 10
- Number of coins per spin: 100
- Coin value x number of coins = bet amount per spin
- 1.00 euro x 100 coins = 100 euro per spin
If you bet 100 coins per spin, with a coin value of 1 euro, it goes without saying that the money will disappear quickly. Therefore, you should think carefully when choosing coin value and bet level.
House Edge: A question of repayment
When it comes to slot machines, it is more common to state the payout percentage (RTP) than house edge. RTP is short for Return To Player, and says something about how much money you can expect to lose when you play on the same slot machine over time.
Here, we call RTP theoretical repayment. The reason why it is called a “theoretical” payback is that it will not necessarily correspond to the actual payout a single player will be left with after a few rounds of play. On the other hand, it is correct to assume that the theoretical payback will be approximately equal to the actual payback if you play on the same slot machine for a long time.
A typical RTP percentage ranges from 94-98%. This means in theory that you should be able to run 100 spins worth €0.10 per spin and be left with everything from €9.40 – €9.80 on average. In other words, a loss of €0.20 – €0.60.
In reality, you may be left with far more or less than this, but in the long run, the theoretical and actual repayments will probably be almost the same. It also means that you will always lose on slot machines in the long run. But if you are really lucky, you can run away with a huge jackpot long before that time – and that is exactly what we casino lovers dream of, is not it?
General slot machine strategy 
Since slot machines are random, it is impossible to create a strategy, but there are some tips that can be used to make the most of your experience. As previously mentioned, it is important to choose the right machine. There is not much point in playing on a machine that pays out 80% when you can play on one that pays out 95%.
Bet on multiple paylines
In the vast majority of cases, it will pay to play on all paylines at the same time. The more paylines you bet on, the more chances of winning you have per spin. Thus, it is better to play on several paylines with low coin value, than to play on one payline with high coin value. Provided your goal is to win as often as possible. If you would rather maximize the size of a possible win, it may be worthwhile to play on fewer pay lines, and rather increase the coin value – because an increased bet amount gives an increased win.
Play with a higher bet level
If your wallet allows it, you should play with the maximum bet since the payback percentage tends to increase along with the bet in some games. In addition, the size of the bet will correspond to the size of any winnings. In other words: The more you bet per spin, the bigger the payout will be. On jackpot machines, there is often a requirement to play with the maximum bet or at the maximum level to qualify for the giant jackpot win.
Check if the casino has a VIP program
If you tend to gamble regularly, you should check with the casino if they have a loyalty program. The more you play on the slot machines, the more complimentary items or points you can earn over time. These can be points that can be redeemed for cash, spins or gadgets. At a real, land-based casino, you can get free drinks, food or even free credit to use on the machines.
General strategy for slot machines
Since slot machines are programmed with random number generators (Random Number Generator), there is little, if not anything you can do to influence the outcomes of each spin. But there are a few other things you can keep in mind when playing:
- Make sure you know the rules properly
- Keep your tongue in your mouth when it comes to coin value, number of coins and paylines
- Choose the slot machines with the highest payout percentage (RTP) and with the right volatility for you.
Slot machine games with jackpots
A jackpot slot is a slot machine with a big win that you can win if you hit just the right combination of symbols. All classic slots and video slots today have a predetermined jackpot, unless you are playing a progressive jackpot slot – something we look at a few sections further down. In the regular slot machines, the jackpots are stated in advance, so you know how much you can win at the maximum. You can also get winnings with other symbols and combinations, but preferably smaller amounts.
An example of such a jackpot slot is Jackpot 6000: This is a very popular Norwegian slot machine that draws its inspiration from an old acquaintance: Jackpot 2000. The predecessor was placed around on shop and kiosk floors in Scandinavia until 2007. Now it can be found below the name Jackpot 6000 at online casinos that deliver games from NetEnt and Betsoft. As the name suggests, it is possible to win as much as 6000 coins on this slot machine. And with a maximum coin value of 1 euro, this will at best be a win of 6000 euros!
Note that you sometimes have to make a maximum bet to be eligible to win the jackpot. This means that you must play with the maximum coin value on all paylines. Make sure you know all the rules for jackpot slot machines so that you are not “cheated” for a big win!
| Review | Jackpot | Play Now |
|---|---|---|
 | Mega Fortune (€1,000,000+) | Caxino Casino |
 | Hall of Gods (€1,000,000+) | Spinz Casino |
 | Arabian Nights (€1,000,000+) | Wheelz Casino |
 | Mega Joker (€50,000+) | BitStarz Casino |
 | Major Millions (€100,000+) | Gaming Club Casino |
 | King Cashalot (€100,000+) | Zodiac Casino |
 | Mega Fortune Dreams (€1,000,000+) | Leo Vegas Casino |
 | Wheel of Wishes WowPot (€2,000,000+) | Spin Galaxy Casino |
 | African Legends WowPot (€2,000,000+) | Royal Vegas Casino |
 | Mercy of The Gods (€10,000+) | Voodoo Dreams Casino |
 | Cosmic Fortune (€10,000+) | Chipz Casino |
 | Divine Fortune (€10,000+) | NYSpins Casino |
 | Mega Moolah (€2,000,000+) | JackpotCity Casino |
 | Mega Moolah Isis (€2,000,000+) | All Slots Casino |
Slot machine with progressive jackpots
By a progressive jackpot, we mean that the jackpot grows as players make deposits. There is no limit to how many deposits can be made, so it can grow really big before someone wins it. Here it can quickly be a question of dozen of million euros in the jackpot.
The more popular the game, the faster the pot grows. And the person who wins, in the end, can win really big. There are many examples of people who have become multimillionaires with the help of progressive jackpots. But remember that the number of people who have tried this and failed is much, much greater.
When the jackpot is won, the starting value is reset and it all starts again. The initial value can be anywhere from a few hundred euros to several thousand. Joker Millions, Arabian Nights and Mega Fortune are examples of such progressive jackpots. Find out more about them by clicking on the name.
Online slot machines for free: Test before you buy!
Did you know that you can play online slot machines for free online?
Many online casinos offer so-called demo versions, or free versions of their slot machines, ie versions where you can test the game with play money. The winnings you win are of course also with play money, so you will not get rich (but not poor either).
The free versions give you the opportunity to get to know the game before you start betting money. It is also a great way to learn the rules, and get an overview of what bonus features the game has and how often you can expect to see the winnings, as well as how big they are.
Tips when playing on slot machines 
When you get free spins
Be aware when playing with free spins and bonus money, that wagering requirements may be different than with regular winnings! Often, the wagering requirements for winnings won with free spins are higher than otherwise.
If you win a really big win, it means that if you won it with free spins, you will probably have to play through the money more times than if you had only played with real money. And it's sour if you did not realize it beforehand!
Therefore, be sure to check the bonus terms before accepting and playing with a bonus (or free spins).
Theoretical payback percentage (RTP)
Think about the theoretical repayment percentage (the probability of how much you will get back from the money you bet, read more about this long on this page, under House Edge: A question about repayment.
The average RTP for online slot machines is around 95%, while the very best are over 98%. To be absolutely sure that you get the most for your money, you should therefore check out where you get the best theoretical percentage, so that you know where you are playing where it is most profitable. You do this by clicking on the info button on the game (often marked with an “i”).
As a rule of thumb, you might think that most slot machines from the game manufacturers NetEnt and Microgaming have a solid RTP.
Progressive slot machines
Due to the theoretical payback percentage, one often gets a little split when it comes to progressive slot machines as we mentioned earlier (see “Slot machines with progressive jackpots”).
The jackpots can be up to tens of millions of euros, but due to these jackpots, the theoretical payback percentage decreases. The whole point of these games is that the jackpots should be able to build up and become big. Then they can not give out small winnings as often as regular slot machines.
If you manage to win the jackpot, you have received a hefty payout for your bet, and the RTP will be unimportant. But this is still something to keep in mind when you play: There is a greater chance of losing more money on progressive jackpots than there is with regular slot machines. On the other hand, a traditional slot machine will never be able to give such big wins!
Bonus game
Not all slot machines come with bonus games, but more and more of them. The bonus games are usually activated when you have collected a certain number of points or a special symbol combination lands on the reels.
Such bonus features give you the chance to further increase your winnings. Most often, you then have to choose between several options.
In Castle Builder, for example, you must choose which suitor the princess will marry when your castle is finished. And in Fairytale Legend: Hansel & Gretel, you get to pick out which candies you want to steal from the witch's gingerbread house (see photo).
Last tip: Play wisely!
Slot machines are primarily designed to be entertaining and fun. Although many of them are designed with missions and overall goals, it is important not to get carried away. Therefore, we want to emphasize that you must always remember to give while the game is good.
If you can do it, you can enjoy the game many more times, because you can afford it. If, on the other hand, you get carried away by betting for more than you can afford to lose, or trying to win back lost money, you start moving on very thin ice.
Do you notice that you have let it go a little too far: stop! And if you can not stop: Seek help! All reputable online casinos can facilitate the gaming account to make it easier and safer for you to play. They can, for example, set bet limits or time limits. In many cases, you can also set these limits on your own, via built-in tools in the casino. They can also guide players to organizations that offer free and anonymous help to people with gambling addiction. Use these opportunities.
Who makes the best slot machines online? 
Want a quick way to find the best slot machines? Check who is behind the game!
When game developers become big and famous, it's because they are good at what they do. If you choose a game based on who made it, the probability is high to find one you like. As you get to know the vendors, you will actually be able to recognize the vendor of specific games! Because everyone has their own style, and often has characteristics that set them apart from the competition.
Below you will find an overview of 6 of the largest and most well-known game developers who make slot machines, as well as a brief introduction about each of them. If you want to find out where you can test their games or learn more about the developers, click on the link for each developer.
Net Entertainment (NetEnt)
Net Entertainment is the gaming producer that first came on the scene, and launched online slot machines almost immediately after the ban in 2017. The investment was a success and led to most online casinos signing agreements with them. The company continues to grow, and along the way has won a number of prestigious iGaming awards.
NetEnt is known for its large, progressive jackpots, live games, as well as ultra-popular titles such as Starburst, Gonzo's Quest, and Dead or Alive.
Microgaming (Quickfire)
Microgaming is one of the top game developers in online gambling. The company started back in 1994 with their first online casino. Since then, they have worked to innovate the Nordic gaming market with innovative products and functions. Today, Microgaming delivers games to many of the best online casinos.
This developer delivers online card and table games and not least live games, but they are probably best known for their slot machines and progressive jackpots. Immortal Romance, Thunderstruck and Mega Moolah are good examples.
Betsoft Gaming
The first Betsoft games were launched in 2010.
“Our team is constantly developing innovative platforms that aim to bring the iGaming industry into the twenty-first century. With modern technology and skilled professionals, we create fantastic solutions across various mobile devices »- quote from Betsoft's website
Betsoft is known for offering 3D games with very good graphics and titles based on current movies and series.
Yggdrasil Gaming
Yggdrasil Gaming is a company that first came on the market in 2013. The developer went from being an underdog to one of the industry's most respected and reputable suppliers within a few years. They managed this, among other things, by focusing on the Scandinavian gaming market.
Yggdrasil is probably best known for its slot machines, which come with strong concepts, video clips, their own bonus features, and good graphics. We can highlight Vikings Og Berzerk and Jungle Books to name a few. But you will also be able to find more lottery games provided by this developer.
Rabcat
Rabcat was founded in 2001, and produces many types of software. With customers such as Microsoft, Disney, Siemens and BMW, the company has made a strong mark, and is considered one of the leading manufacturers of software, quality games and applications in the international gaming industry.
The developer delivers slot machines, video poker, table games and innovative 3D games based on its own brands. They are probably best known for slot machines with unique game concepts and good graphics. Some examples are Castle Builder, Moby Dick, Gnome Wood, and Forsaken Kingdom.
A little history: The very first slot machine games
There is a long history behind slot machines and there is no doubt that we have come a long way since the first, land-based machines appeared in the 1930s. But the very first slot machine similar to the ones we are used to today was invented in the late 19th century in a private garage. It was called the Liberty Bell Slot Machine and was about landing three bell symbols in a row. The game became so popular that several companies copied the invention, which created the breeding ground for the gaming market we know today.
Slot Machine Game Is Age-Old Fun 
It is odd how many people log onto great gaming sites and they are happy to discover what they think is a new game on the land. What they do not realize is that slot machine games are more than a century old, and that the slot machine was designed purposely for gambling. In short, the idea of a casino is not new either. There may not have been sophisticated incentives such as offers of free spins, but the game was well-received. It is interesting to note that whereas in present-day slot machine games players anticipate hitting the jackpot that is normally in several figure dollar digits, in the very early days, gamers were happy to be paid in gum. This, obviously, discloses that gum was a luxury item at some point in time.
Different Names For Slot Machines
For those players who have not thought much about slots beyond the site they play on, they may not know that fellow players from different parts of the world refer to the same game in different terms. In Australia, for example, they call slot machines poker machines, while in Japan they refer to them as either pachisuro or pachislo. In New Zealand, they pass for pokies. However, the principles governing slot machine games are basically the same everywhere.
In fact, differences have become almost irrelevant now that the slot machine is online. This means they are open to players from diverse backgrounds. When a player wants to play from a casino on a website hosted in the UK, US, or any other country, there is normally no requirement for the player to enter their nationality or cultural background details during registration or at any other stage. So, clearly, slot machine games today are a global activity.
How It All Began
The pioneer slot machine was made based on the fundamentals of the game of poker; poker game as played with cards. Charles Fey, who is the man behind this invention, created the gaming machine with three spinning reels. So, from inception, slot machine games were to be played by spinning. Things were not so sophisticated then, and therefore it is unlikely that anyone could talk of a casino or a recreational facility of such magnitude. Even when the actual games began, it is unlikely that anyone could imagine giving offers to players, such as what happens today. Anyone speaking of free play rounds, as happens in the offers of free spins, might have been thought crazy.
Still, even with a lot of things related to the slot machine games being rudimentary, the inventor, Fey, still managed to give the slot machine five distinct symbols, which are spades; diamonds; horseshoes; hearts; and finally, the Liberty Bell.
How The Jackpot Was Determined
Having some knowledge about your favorite game is likely to give you a better appreciation of the fun it brings. In those many years ago when Fey’s machine had the name Liberty Bell slot, the Liberty Bell was a jackpot symbol. In fact, whenever the Liberty Bell symbol appeared three times in a row, the player had won the highest possible amount for the jackpot.
And, of course, the winning happened without the participants using freebies like free spins no deposit as often happens today. In any case, things were plain simple and straightforward then, with such fun games being few, and participants being very few also compared to today’s gaming population. With such a long and interesting history, it is not surprising that slot machine games have remained this popular worldwide.