Online casino slot games are popular for a reason: They are easy to play and still offer big payouts. Unlike other casino bonus games, you do not need “experience” to play online slots. Even if you have not played a single casino game before, you can start playing slot games like a “pro” in 5 minutes: They are that easy to learn. You may not win a poker game against a professional gambler or may not beat the dealer at blackjack unless you learn complex tactics and strategies. Slots online, on the other hand, are “equal” games for everybody: You have the same winning chances like all the other players, no matter what their experience is. Therefore, it is easy to understand why they are the most popular online casino games looking to play more popular games? Come read our online casino games guide. But even if they are the easiest games to play at online casinos, you still need to learn how they work and which features they have. Moreover, you need some pointers in order to maximize your winning chances. And this is exactly what we are going to do in this online slots guide: We will tell you everything you need to know and make you the ultimate online slot player. Let’s start!
Our Best Casino Picks
Before starting our slots guide, why don’t we show you a list of the best online casinos to play all kinds of slot games? Let’s be clear: This is a free slots guide, which means you can use it to play all kinds of free slot games. However, the online slot tips and other explanations in it can be used to play real-money slots too. And when you want to do this, you should play at the best casino sites. To save you the trouble, we already picked them: Below, you can see our recommendations.
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What Is The Difference Of This Online Slots Guide?
If you make a search for “free slots guide”, for example, you will see hundreds –even thousands- of results. This is because it is pretty easy to prepare an online slots guide: List the basic rules, pick a couple of games, and list a couple of general online casino slots tips. That kind of guides are not useful for anything: They don’t contain enough info and their tips for online slots are pretty simple things everybody knows.
So, what is the difference of this slots guide? What do we offer to you? Well, first of all, we will explain all of the slot rules in detail and according to different slot categories. So, no matter what kind of slot game you are playing, you will know what to do: This online slots guide will teach you everything you need to know about every slot game out there. Second, we are players too and fans of slot games. In other words, before preparing a slotsguide, we really play these games for a long time and give you accurate info. In short, we are more than capable of picking the best slot games for you – speaking of which, you can see them below. (A slot guide is not complete without a “best of” list, so we have one too.)
Lastly, the online casino slots tips we include are unique and really useful: We don’t make empty promises. For example, you can be sure that there are no casino tips and tricks slots that will guarantee a winning: If you see such a “guarantee” in a slots guide, you can be sure that it is a lie. However, it is still possible to increase your winning odds by using some casino slots tips and implementing an online slot strategy. Well, we have them both: This online slots guide contains many tips and tricks that will increase your chances.
How Do Online Slots Games Work And What Is An RNG?
We need to start this casino slots guide by explaining the basics. The rules of online casino slot games are pretty simple: There are multiple symbols on reels and your goal is to land the same ones next to each other on a pay line. You need to land at least 2 or 3 symbols to qualify for a payout, and your prize will be determined according to the symbol set you placed. All slots online games work like this, no matter what category they belong to. Take a look at the slot guide section where we explain these terms if they do not sound familiar, they are very easy to learn. You click on the “spin” button, the reels start to turn, and if you manage to land the same symbols next to each other, you get a prize – it is that simple.
But, what happens in the background when you click the “spin” button? This part is important because a lot of the misunderstanding about online slots originate from not knowing how they work. Back in the 60s, when slot machines first appeared in Las Vegas, they were real “machines” that work with cogs and reels. They were like a watch that needs to be wind up: Some of them were not even using electricity. The majority of online slot myths and online casino myths originate from this era because back then, it was possible to estimate when they will make a payout by listening to the cogs and reels, literally.
However, this is not the case anymore: Real money slots work with an RNG (random number generator) software nowadays. (In fact, all casino games online use an RNG software, not just the online slots.) It is a part of the casino software, and all it does is generating random numbers. Each of the symbols in an online slot machine game has a numerical counterpart. When you click the “spin” button, the RNG software generates a random number. And if that number matches the numerical counterpart of a symbol, it appears on the screen. For example, let’s assume that you are playing jackpot slots online:
- You click on the “spin” button and the RNG software generates a number: 10965
- The numerical counterpart of the “wild” symbol is in between 10900 and 11000
- Since it is in the range, the wild symbol appears on the screen and you hit the jackpot
All of these happen in mere seconds (and this is obviously a simplified explanation) but you get the idea: In a system like this, it is impossible to guess the outcome of the RNG software. Even the programmer of the online slot game cannot predict what will happen. Therefore, it is impossible to create a strategy for the best payout online slots UK: It all depends on luck. But you can still increase your winning chances by selecting the correct categories and using some tips & tricks – we will tell you about these below, but first, let’s answer another popular question in our slotsguide: Can you play online slots for real money for free?
Can You Play Online Casino Slots For Free?
Yes, all online slots that pay real money can be tried free of charge: You don’t actually need to spend a single penny. This is one of the biggest advantages of slot games – you can try all of them without taking a financial risk and find out the best ones according to your needs. And you can do that even at online casino sites if you pick the right ones. Some casino online websites allow you to play free casino slot games with bonus rounds even without becoming a member. Just visit the website, pick among hundreds of online slots machines games, and click on the “play” button: The game will load instantly and you can try it as long as you want with a virtual balance.
Cloudbet Casino is the best website to do this. It offers more than 500 high-quality online slots and all of them can be played free of charge. Just visit the site, pick a game, and click the “demo” button – that’s all. We recommend starting with the most popular slot machines, but you can try the entire collection and play all the online slots real money collection without spending any money.
BEST SLOTS CASINOS 
Recommended Online Slots Games
- Starburst: Developed by Netent, Starburst is one of the most popular online slots and can be found in most of the 100 best online casinos for a simple reason: You can trigger the free spins bonus round more than once and multiply your winnings!
- Book of Immortals: If you like ancient Egypt-themed slot games, this one is for you: Embark on an adventure in pyramids, claim the long-lost riches.
- Sizzling 777 Deluxe: One of the best examples of the fruit slot games genre. It is very easy to play and still offers big prizes.
- Lara Croft Temples And Tombs: Yes, that Lara Croft. Adapted from the famous Tomb Raider PC game series, this online slot will offer you an amazing adventure and big payouts.
- Best Penny Slot Machines To Play: Penny slots are one of the greatest way to play online slots without loosing a big sum of money. Come check it out!
And once you are done playing for free, you can become a member claim your casino bonus, which will give a generous BTC bonus amounting to 100% of your first deposit up to 5 BTC. Sounds good, right? Take a look at our casino reviews section to find more casino sites that offer online slots bonuses. We offer you an international online casino list, which means no matter where you live in the world (United States, United Kingdom, Germany, Italy, Sweden, Estonia etc.) we can find the best bonus slots for you.
Free Casino Slots Vs Online Slots Real Money: Which One To Prefer?
You may think that the obvious answer is online slots that pay real money, but you are wrong, actually. This is a “trick” question because you do not need to pick a single category. Both slots can co-exist together, and you should play all of them, without picking a favorite. But why?
- Free slot games are exactly the same as online slots for real money. Their rules, symbols, and winning chances are the same. The only difference is your balance – free online slots don’t cost a thing to play and won’t award you real money.
- Literally, dozens of new slot games are released every month. If you want to try them all, you will need a big budget. By using their free versions, however, you get to play all the latest slots and learn about them, without affecting your gambling budget.
- Finding the best online casino real money games that appeal to your needs will take a long time. You should spend money only on slot games you like. The free game casino option allows you to do this: Try the entire online slots collection of a casino site for free, pick the best ones, and keep playing them with real money.
In short, even if you are ready to spend real money, you must play free slots online first, in order to learn the rules, practice, try all the latest slot games, and find the best ones that suit you the most. You don’t need to pick a single option: Use both to your advantage.
So, which free slots with bonus games are the best ones to play in 2021? Take a look at the list slot machines below: We already picked them for you. We highly recommend starting with these online slots, because you get to try every slot category (which we will explain below) and find about all of your options. Plus, these popular slot games can be found in almost every online casino and you can play them from mobile too. Let’s take a look at our list first, then we will continue our online slots guide.
Top Casino Slots To Start With: Best Online Slots In 2021
- Davinci Diamonds: Da Vinci Diamonds includes Tumbling Reels feature, which gives you another chance to win a prize after a winning spin.
- Bonanza Slots: This is a Megaways slot game, so the number of pay lines is virtually unlimited (so is your winning chance).
- Starburst Slot: If you like free spins feature, you should prefer Starburst because it includes hundreds of them which you can trigger multiple times.
- Book of Ra: Probably the most famous ancient Egypt-themed slot game. If you like it, don’t forget to try the sequels too.
- Reactoonz: Cute aliens, big explosions, bigger payouts: One of the best online slots of Play’n Go.
- Age of the Gods: You can enjoy the Wild Winds feature on this one, which carries the wild symbols onto other reels.
- Thunderstruck II: Sequel to the famous Thunderstruck slots, this one includes 100 pay lines and four different bonus rounds.
- White Orchid Slots: White Orchid is developed by IGT and it offers 1.024 ways to win with the patented MultiWay feature.
- Triple Diamond Slot: The perfect example of the fruit slot games category. You can win 1.199 times of your total bet.
- Golden Goddess Slot: Another classic IGT game, which includes “stacked symbols” feature that allows you to multiply your winnings.
Remember that you can play all of these games (and more) for free at our recommended online casinos. Again, take a look at our online casino review section to see a list of them.
Features Of Online Slots: What You Need To Know
Now, we can start talking about the features of online slots. By learning more about them, you can easily master all kinds of slot games, no matter which category they belong to. Note that the following features are common in all types of online slots, so knowing more about them is of crucial importance.
Symbols: Also known as “signs”, symbols are the “play cards” of online slots. Each slot game has them, and their numbers can be different. For example, a fruit slot game can include 8 symbols in total but you can find 20 symbols in a video slot game. No matter how many symbols there are, you should know the following things about them:
- They are based on the theme of the online slot. In a nature-themed slot game, for example, you see the pictures of wild animals as symbols.
- Each one has a different payout. There are high-paying symbols and low-paying symbols, you need to search in order to find the best paying online casino (we even have a list for the best payout online casino UK sites). Your prize will be determined according to this. Landing the same 2 or 3 symbols next to each other will always give you a prize, but its amount will be determined according to which symbols you placed.
- There are three types of symbols: Pictures, play cards, and special ones. Picture symbols contain a picture, as the name implies, and they have high payouts. Play card symbols use the signs of a deck (10, 9, Q, K, J) and they pay less. Special symbols are wild, scatter, and bonus, which we will explain below. Special symbols can activate a bonus feature or increase your winning chances. They are used in slot games with bonus rounds.
Paylines: These are actual lines that connect both sides of the reels. You can see what they look like after scoring a win: They are not straight lines, more like zig-zags. They are pretty important actually: The more lines there are, the better your winning chances will be. So you are more likely to win at online slots that contain 1.024 lines, for example. However, this has a price: The cost per spin will be much higher for this high limit slots, as we will explain below.
Bet Level: Your minimum and maximum bet amount. It usually starts at 0.01 coin and can go as high as 100 coins. The most important thing to know about bet levels is this: While playing online slots, you place a bet per line, not per spin. Let’s say the minimum bet amount is 0.01 coin and there are 20 pay lines. Since you will be betting on all of the lines, the real minimum bet amount will be 0.20 coin (0.01 x 20). The same thing applies to the maximum bet level too. So while your winning chances will be higher in a 1.024-line slot game, the cost per spin will be higher too, for this reason.
Bonus Rounds: Video slots, jackpot slots, and 3D slots offer this feature, classic fruit slots usually do not have a bonus round. This feature is usually a free spin round, where you get to spin the reels free of charge for a certain number, i.e. 20 times. To trigger the round, you need to land a special symbol, and usually, the scatter symbol. However, the bonus round can also be a mini game where you try to guess the sign of a closed play card or a guessing game, like “pick me” rounds. Bonus games slot machines will always give you a cash prize and sometimes include the highest payout. You cannot choose when to activate them, they trigger automatically once their conditions are met (i.e. landing three scatter symbols).
Online Slot Terms
In addition to these features, there are some commonly used terms in online slot machines real money games. You will hear these terms pretty often and we will be using them in this guide too, so let’s explain their meanings. Some of them are of crucial importance because they literally determine your winning chances.
RTP: Short for “return to player”, this term is the most important of them all. The RTP rate shows how much you will lose in the long run, and for the same reason, what will your winning frequency be. Here is an example: If the RTP rate of an online slot game is 97%, this means you will win back 97 EUR of every 100 EUR you deposit. In other words, your losses will be limited to 3 EUR (100 – 97). And since this is a low figure, your winning frequency will be quite high too. Naturally, your goal should be finding the slot games with the highest RTP percentages. However, do not confuse this with the winning chance. RTP rates do not determine what your winning odds will be, they just show your maximum loss. And naturally, if this is a low figure, you will win more often, but the RTP rate does not “guarantee” winning in any way.
Payout: A list that shows how much coins the symbols pay, for landing them next to each other. It also shows what your maximum prize money will be.
Paytable: Another important term and a literal table, which you need to check before starting to play. Every slots online contain a paytable, which can be launched by pressing the same named button (or a button that says “help”, “view payout”, etc.). This table includes:
- The payouts of symbols
- The general rules of the game
- The special rules of the game (conditions of triggering a bonus)
- Maximum winning limit
- RTP rate
So, when we say “play slot games that have the highest RTP rates”, we mean that “open the paytable first and find out what the RTP rate is”. You will also learn how to play the game & what to look out for by reading this table.
Wild: A special symbol that is pretty common in video slot games. Fruit slots usually do not have any special symbols, but almost all other slot categories have one. The primary feature of this symbol is to substitute any other symbol. So, for example, let’s say landing three 10s will pay 50 coins, but you managed to land only 2 of them. By landing a wild symbol next to these two, you can complete the set and qualify for the payout. Wild symbols do not substitute other special symbols (such as scatter) and they usually have the highest payout.
Scatter: Scatter may be the most important special symbol in all online slots. There are two reasons for this:
- Unlike other symbols, scatters pay no matter where they land on reels. So you don’t need to place them on a pay line. As long as they appear on the screen, they will make a payout, whether they are on a pay line or not.
- Scatter symbols are primarily used to activate the bonus rounds. For example, landing three scatter symbols anywhere on the screen will launch the free spins round. Landing more than three scatters will increase the number of free spins in that round.
Bonus: This special symbol can be seen in slot games that have a jackpot prize. To win that big prize, you must land bonus/jackpot symbols on the pay lines. Usually, you need to land 5 of them and they do not have a separate payout. But if you want to win the jackpot, you must always look out for these symbols.
No deposit slots: This is not a standard slot term – it is actually an online casino bonus. Some online casinos give you free spins upon registration and without a deposit. You can use these spins on pre-selected slot games and still win a cash prize. Online slots real money no deposit is a term that is used to explain this promotion. You can find lots of casino sites that offer such a bonus in our online casino reviews section.
Online casinos no downloads: Another term that is used to explain the category of an online casino. Simply put, online casinos can be instant-play or “download”. Instant play casinos work on browsers and you can play all of the online casino slot games instantly, without downloading any software (hence, the term no download comes from). Download casinos, on the other hand, require the installation of a program.
Slot Games Categories
We have learned the features and terms of online slots, but there is still one more thing to talk about: Slot game categories. While the overall goal is the same (landing the same symbols next to each other), different types of slot games offer different kinds of experience. And can be guessed, different winning chances! Yes, some slot games offer higher winning odds than others. Let’s see the list of all slots online categories and explain them one by one.
- Classic: Also known as “fruit slots”, this is the most basic version of slot games. They are also the oldest type of slots. Classic slot games have fewer pay lines and symbols, they also do not have special symbols and bonus rounds. Yet, they offer quite satisfying payouts, which we will explain in detail below. Since they have the simplest rules, classic slot games are the best for beginners. However, note that their graphics quality is also very low.
- Video: Most of the new casino slots games fall into this category. Video slots are the most popular version of slots online: They have advanced graphics, lots of pay lines (20 to 1.024), increased payouts, special symbols, and bonus rounds.
- 3D slots: These are the same as video slot games, but their graphics quality is amazing. Usually, they are the adaptations of Hollywood movies and offer CGI-quality visuals. We recommend picking 3D slot machine games for PC; as mobile devices usually do not have the hardware power to run them at high quality.
- Jackpot: Classic or video slot games that include a big but fixed prize. The prize amount is the same no matter how many players tried their chances on the game. If you like to play jackpot slots, you should prefer them, and not the progressive jackpot slots – we will explain why below.
- Progressive Jackpot: Same as the jackpot slots, but this time the prize pool is dynamic and progressive. This means with every game played, the prize in the pool keeps increasing. Sometimes the prize amount can reach millions of dollars. The “world-record payouts” you see in the news come from progressive jackpot slot games.
- Multiplier: This means the slot game (no matter what category it is) pays in multipliers, rather than coins. Here is an example: A standard video slot game has a fixed payout amount for its symbols, i.e. landing the wild symbol will pay 200 coins. A multiplier slot game, on the other hand, has just a multiplier number such as 200x. This means the payout is 200 times total bet: There is no fixed number.
- Multi-Line: These slot games are usually seen in brick-and-mortar casinos but they have online counterparts too. Multi-Line slot games have two screens: You start to play at the bottom screen which has a low payout. Once you reach a certain prize amount, you continue to play at the top screen, which has a higher payout. The rules are the same, and both screens even use the same symbols, but they pay differently.
- Virtual Reality: They are probably the future of all online slots. These are real 3D slot games, which are played with a Virtual Reality goggle. You spin the reels with hand movements and the graphics quality is amazing, as can be expected. And purchasing a 99 USD VR goggle is enough to play them, no expensive hardware needed. Forget PC, forget mobile devices: In the future, we will play online slots that pay real money with these goggles.
Casino Slot Tips And Tricks For Real Money Slots
Once again, due to the working principles of the RNG software, it is impossible to create a fully-working strategy for online slots. Systems such as high limit slots strategy, for example, does not contain a set of rules that needs to be followed exactly. Instead, they are based on general advice and suggestions, based on the type of slot machines and their RTP rates. So, while we cannot provide you with guaranteed strategies like we did for the live casino online tables and card games, we can still give you some tips and tricks.
- Classic slots are better. They are better because their cost per spin values are low. Since they have fewer pay lines, the minimum bet level is quite low. This means even with a small budget, you can spin the reels for hours. Doing so will give you additional chances on winning. For example, if you have a 100 EUR budget, you can spin the reels of a video slot game 20 times. But with the same budget, you can spin a classic slot game for 80 times.
- RTP is the most important thing. Always check the RTP percentages and prefer slot games that have a 95% or higher RTP value. The higher the better.
- Read the review first. Before starting to play, read the online slots reviews for that game. By doing so, you will learn the most important things about that game (such as is it worth playing, the rules, how the bonus rounds work, etc.) beforehand.
- Join a slots tournament. Slots tournaments at online casinos will offer you a grand prize for a thing you are already doing: Playing slot games. So why not join a tournament about them and try to grab the grand prize? Joining is free and all you need is luck to win, so make sure to join all of the slot tournaments you can find.
- Progressive jackpots are not that good. Progressive jackpot slots have very low RTP rates. There is a reason why the prize amount is that big: This means many players already lost their bets and their losses are added to the pool. In short, prefer free progressive slot games if you like this particular category. Your winning chances will be very low if you play them with real money. Fixed jackpot games offer much higher RTP rates, prefer them instead of a progressive prize pool.
- Finding a good free spins bonus will be the best thing you can do. Getting hundreds of free spins right at the beginning will be very advantageous for obvious reasons. Prefer online casinos that offer such promotions. And to find such casino sites, keep reading: We are explaining how you can find the best slot casinos below.
How To Find The Best Online Casino To Play Top Slots
Starting with our recommended online casinos will be a good idea: We already examined them and confirmed that they offer the best bonuses and the latest slot games. While reviewing them, we used the following criteria and you should do the same too.
- The casino site must be licensed and legal, period. Never play in an unlicensed casino website.
- Casino Payments. Make sure there are lots of payment methods supported. Learn more by reading our “payment casino” guide
Online slots PayPal Casino games, for example, will give you the chance to use your PayPal account for deposits and withdrawals. The payout process should be as easy and as fast as possible.
- Game Providers. And of course, the online casino must be working with top providers in order to offer you high-quality online slots. Microgaming, Netent, IGT, Novomatic, and Play’n GO are just a few of these providers. Always check how many slot games are available and who provides them.
- Make sure that you are getting lots of free spins at the start and the wagering rate is low. We explained free spin bonuses in lots of other articles, so take a look at them too.
Pros And Cons Of Casino Slot Games
- Suitable for everyone
- Hundreds of different themes
- Available at every online casino
- Good payouts
- Excellent mobile compatibility
- Can be played for free
- Some of them have low RTP rates
- You cannot become better by playing more: There is no such thing as “professional slot player”
Online Slot FAQ
Play Slot Games With Bonuses Right Now!
Well, now you know everything there is to know about online casino slot games. It is time to start playing online slots: Find or pick an online casino from our lists, create an account, and start spinning the reels today! Online slots for real money offer you hours of fun and satisfying profits, so you should embark on this journey right now. As always, we will be here to help and guide you along the way or to let you know how much you can cash out at a casino or how Spanish 21 card counting or tips about 20 Card Keno Strategy. Good luck and may the reels turn in your favor!