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Why Play

If you’re looking for a reliable platform offering a diverse range of free slots, then is the way to go. There are over 2700 slots available where you can try your luck. You don’t need to deal with the hassle of sign-ups, downloads or deposits either.

Additionally, recommends only the top game providers that offer the most high-quality, reliable and safe free slot machine games. 

At You can play the most popular slot games for free daily and earn rewards for it, thanks to Book of Slots rewards system.

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Free Slots vs. Slots for Real Money

If you’re new to the world of slot machine games, you may be wondering whether to stick to the free-to-play version or take a gamble by betting real money. Here are some things to consider when choosing between free slots vs. those requiring real money.

💸 Free Slots

  • Test out different strategies without losing any real money.
  • Practice playing particular slots to learn how to unlock hidden mini games and bonus features without spending a dime.
  • Enjoy free entertainment without going through the hassle of signing up.
  • Do not get the chance to win actual cash.

🤑 Real Money Slots

  • Get the chance to win actual cash prizes.
  • Gain access to deposit bonuses and promotions.
  • Potentially win huge sums of money through the progressive jackpot.
  • Risk making a loss on your investment.

How to Play Slots - Things To Remember When Playing Slots

New players might find it confusing to navigate in the world of slots. After all, they can be overwhelmed by the amount of themes and gameplay features. However, playing slots is extremely simple in reality. Moreover, you can play risk-free thanks to the demo version. It is an excellent way to learn winning combinations and bonus features of a particular slot. 

Below, we will go over the most important concepts in online slots. After reading this short guide, you will be ready to spin your first reels. 

What is RTP and Why Is It Important?

RTP stands for return to player. It is a crucial parameter in any slot game. As the name suggests, it is the expected value of a player’s winnings. It is also sometimes referred to as house edge. For example, if the RTP is 95%, then for every $100, you are expected to receive $95. 

It is important to mention that RTP is a long-term parameter. This means that a given slot can return less or more than the expected value for a short period. However, the RTP will always even out in the long run. 

As you can see, RTP directly determines the player’s expected winnings. Therefore, it is crucial to consider RTP when choosing which slot to play. Try to pick games with the highest return percentage. This will significantly increase your winnings. Besides that, it lets you stay in the game longer. 

Volatility and RTP

Slots also differ in their volatilities. This parameter reflects the game’s average win frequency and size. For example, slots with high volatility will pay out big wins but rarely. Low volatility slots, on the other hand, will have frequent wins in quick succession. It is important to note that the slot’s volatility doesn’t correlate with RTP. Volatility simply shows the frequency at which your wagers are returned. 

  • Low volatility slot will usually have a more predictable gameplay, with small wins on practically every spin.
  • High volatility slots will build suspense until its big win.

It comes down to the player’s gameplay preferences when deciding on the slot’s volatility.

You can find excellent slots regardless of their volatility. For example, Towers of Olympus is a famous high volatility slot. Starburst is a good option for enjoyers of low volatility. Finally, Gonzo’s Quest sits right in the middle with its balanced risk and reward. 

Graphics and Theme

Slots come with all sorts of themes. Casino graphics continue to develop with each year and themes continue to get better. A visually pleasing slot is more likely to attract and retain the player’s attention. Moreover, many slots are influenced by pop culture, such as famous bands and movie characters.

When browsing the slot menu, you will notice that certain themes are more popular than others. For example, Ancient Egypt is an extremely widespread style. Many games also feature books as their symbols. Not to mention the original fruit machines that are still relevant today. 

Here are some slots with outstanding graphics that you can try today:

Hit Frequency

This setting determines how often a player wins per a certain amount of spins. It can be calculated by dividing the total winning combinations by the total possible combinations. Hit frequency is usually expressed as a percentage. 

In most cases, slots with higher hit frequency will have a lower jackpot. Therefore, slots with higher hit frequency will also have a lower volatility and lower risk. You should always consider hit frequency together with RTP. This way, you can estimate the slot’s payout amount and frequency. You can also get an idea of the slot’s hit frequency firsthand by trying it for free in the demo mode. 

Bet Sizes

Just like in any casino game, bank management is crucial in online slots. Each game will have a set amount for the minimum and maximum bet. This number can vary between different slots, so it is important to choose games according to your budget. 

For example, slots with high minimum bets will be more suitable for high rollers, looking for huge payouts. Meanwhile, lower minimum bets allow for less riskier gameplay, which can be better for a new player. 


Slot developers will usually incorporate certain bonus functions into their games to keep the gameplay interesting. After all, spinning reels can become repetitive. Free spins are the most common bonuses. As the name suggests, this feature lets you spin the reels risk-free. In most cases, you can get free spins by collecting special symbols. 

Bonus buy is another frequent addition. For an extra fee, players have a chance to participate in a bonus round. This can entail free spins or even a separate mini-game. It is important to analyze the potential benefits of such a bonus buy and whether it outweighs the risk. Some slots can have more favorable bonus buy conditions than others. 

📱 Mobile Slots

Mobile slots work well on both iPhone and Android devices. Usually, all software providers make sure their games are compatible with all types of devices. You can even play on Windows phones or Blackberry using special casino websites.

So, you don’t need to worry if you don’t have the latest iPhone or Android - offer the best online slots that are compatible with all devices and screen sizes, allowing you to have a smooth gaming experience no matter where you are.

NetEnt, Microgaming, and Playtech are some of the highly-acclaimed software developers providing mobile slots. Their slot games work smoothly on all kinds of mobile devices, and are verified to be fair and safe. These developers also produce slots with exciting and diverse themes that offer players an enjoyable gaming experience. 

Before you start playing slots on your mobile device, whether it's just for fun or with real money there are some things you should be aware of. The gaming experience on a portable gadget may feel somewhat different.

The slot games are generally not available to download, and are supported through Flash Player or HTML5. However, you should be able to play on any of the browsers available on your device. Just ensure you have a reliable internet connection.

Being able to play slot games on mobile devices can be quite convenient, but it is important to consider all the pros and cons.

✅ Advantages of Playing Slots on Mobile Devices

  • Convenience to Play Anywhere, Anytime. You do not need to be stuck at a computer or spend excessive time and money to go play slots at a casino. Mobile slots let you use your tablet, laptop or phone so you can play with ease at home or on the go.
  • Play According to Your Schedule. Mobile slots provide players 24/7 access to play whenever it is convenient for them.
  • Bonus Rewards and Extra Incentives for Players. Most slot games on mobile offer players special bonuses and free spins.

❌ Disadvantages of Playing Slots on Mobile Devices

  • Risk of Gaming Addiction. Having unrestricted access to online slot machines may lead to players spending excessive time and money on the games.
  • Security Vulnerabilities, Data Breaches and Fraud. Depending on the platform, there is a chance for players to become the target of hackers seeking to steal personal information, therefore, never download casino apps from unknown third party services.

Android Slots

Practically all online slots can be played on Android devices. This includes both free and real money versions. Moreover, mobile slots are identical to their desktop counterparts in terms of graphics, functionality, and responsiveness. 

You can try out online slots for free at without downloading a separate app. These slots are fully supported by Android devices. 

iPhone or iOS Slots

Just like Android, iOS devices support most online slots out there. This includes demo and real money versions. You can enjoy amazing graphics and high processing speed on any iOS device. 

If you want to try out online slots for free, then is the place for you. It lets you jump right into action from your mobile device without any downloads. 

🔥 Best New Slots to Play for Free in 2024

There is a wide variety of online slots available to players nowadays. However, due to this massive supply, it can be difficult for new players to find the best slot. Luckily for you, we have hand-picked a detailed list of the best online slots. 

We have used strict criteria in our ranking to rate slots based on their special features, RTP, software provider, and gameplay. After reading through our list, you will have a good understanding of the best online slots out there. 

🥇 Top 1 - Sugar Rush 1000

Sugar Rush 1000 is a popular video slot released in March 2024 by the legendary Pragmatic Play. The candy-themed game is regularly played by casino streamers thanks to its high volatility. The maximum RTP of 97.5% is way beyond the industry average. The 7-7 grid yields memorable moments with frequent scatter symbols and multipliers up to x20,000.  

🥈 Top 2 - Zeus vs Hades: Gods of War

Zeus vs Hades: Gods of War slot developed by Pragmatic Play. The legendary 5x5 slot was first released in May 2023. Fans fell in love with the Greek mythology aesthetic. Besides that, the slot features a x15,000 max multiplier and up to 96.07% RTP. Watch out for the Expanding Wild symbols and watch Zeus and Hades go head to head to increase your multiplier. 

🥉 Top 3 - Bouncy Bombs

Bouncy Bombs by Hacksaw Gaming is known for its surreal and dreamy theme. Even though this game was released in March 2024, it has already earned players’ approval and it is easy to see why. The 96.22% RTP and high volatility make Bouncy Bombs an ideal slot for any gamer. Players can also enjoy special features like cascading wins and bomb multipliers up to x10,000. 

⭐ Top 4 - Samurai's Katana

The Push Gaming slot has a unique theme that seamlessly blends the samurai aesthetic with the cyberpunk genre. Released in March 2024, Samurai’s Katana features 5 reels and 4 rows with 20 paylines. The RTP can reach up to 96,40% with a max win set at x10,000. You can expect exciting features such as Wild Stacks that land fully stacked on the reels. 

 Top 5 - Ripe Rewards

The 5x5 food fruit-themed slot released in April 2024 by Pragmatic Play may seem simple at first glance. However, Ripe Rewards features generous wild symbols and free spin rounds with progressive wins. The RTP can go up to 96.02% with x10,000 max wins available for players. 

 Top 6 - Big Bass Secrets of The Golden Lake

Fans of fishing will love Big Bass Secrets of The Golden Lake with a generous 96.07% RTP and a 5,000 max win. Released by Pragmatic Play in April 2024, it features unique Money Symbols and several ways to get free spins. Watch out for the fisherman’s hook to pull symbols back onto the reels. 

 Top 7 - Chambers of Ancients

Play’n GO released this mythology-themed slot in March 2024. Chambers of Ancients features a solid 96.31% RTP and generous bonuses. For example, you can get up to x20,000 multiplier by collecting 3 or more Key Symbols. 

 Top 8 - The Dog House Dog or Alive

Casino streamers love The Dog House Dog or Alive due to its high volatility. The Pragmatic Play slot features RTP up to 96.08% thanks to its wild and sticky wild multipliers. Players can get up to 10,000 of their bet. Besides that, many gamers enjoy the adorable theme of dogs in the Wild West. 

 Top 9 - Fire Portals

Another recent Pragmatic Play slot is on our list. Released in March 2024, the slot features a magical theme of spells and wizards. High rollers will enjoy its high volatility, as well as RTP up to 96.06%. What’s more, players can get multipliers up to x10,000 thanks to its scatter symbols. Fire Portals also boasts a unique feature of changing paylines, which keeps gamers on their toes. 

 Top 10 - Tombstone No Mercy

Tombstone No Mercy slot was released in April 2024 but has already gained a large following. Developed by Nolimit City, the game has an average RTP of 96.05% and a max win of x16,480. The Wild west themed slot is known for its high volatility and unique art style. Not to mention its entertaining gameplay with outlaw nudge wilds and several free spins.

🎰 Types of Slot Machines

Casino slot machines have been growing in popularity year by year. There are different kinds you can find now like the classic, video, fruit machines, multiple line slots, and slots with progressive jackpots.

Classic slots are the ones everyone has seen, with 3 reels and a lever.. Video slots offer bonus rounds and more reels to spin. Fruit machine types are common in the US and have lots of colorful fruit symbols, but they usually favor the casino more.

Multi-line slots let you bet on many lines at once for bigger wins. And progressive slots have jackpots that get bigger and bigger, often starting at a million bucks, so a lot of folks love playing them.

At, finding the slots you want is really easy. You can easily filter slots by type and features, making it simple to find what you want. There's also a regular filter to narrow down your choices even more.

Classic Slots

Classic slots are the traditional type of slot machines with set symbols, reels and basic winning combinations. They’re known for the images fruits and lucky number sevens. They started in real casinos but are now online too. Some new versions mix old and new features. They’re a great starting point for beginners as they’re easy to understand.

Other games like "Cosmic Cat" and "Sevens and Bars" keep things simple too. They are good for people who like playing on phones or don't want to spend a lot of money. "Cosmic Cat" is set in space and "Sevens and Bars" is about lucky numbers.

You can find high RTP, classic slots to play at

Video Slots

Video slots are different from old-style slots where you pulled a lever. Instead, you push a button. Old slots had physical spinning reels, but now electronic video slots are more common. They can have up to seven reels. Even online slots are basically video slots.

Many players love video slots because of their bonus rounds. These rounds add extra chances to win credits by completing new challenges. These are great for more casual players, or beginners.

Some popular video slots have high Return to Player (RTP) rates, meaning they pay out well. Blood Suckers by NetEnt has been a hit since 2009 with its 98% RTP. Red Tiger even made a Megaways version. Reactoonz from Play’n GO with RTP of 98.71% is another favorite with its cute alien theme and features like transforming wilds. 

Thunderstruck II by Microgaming is a classic Norse mythology-themed slot known for its free spins bonus, having an RTP of 96.65%. Starburst by NetEnt is a simple but hugely popular game with wilds and re-spins and RTP of 96.1%. Book of Ra Deluxe by Novomatic has an RTP of 95.1, and takes players on an Egyptian adventure with expanding symbols in its Free Games feature. 

Video slots are the modern version of old slots, offering more features and chances to win. You can find a wide variety of them at

Progressive Jackpot Slots

In a Progressive Slots game, a part of your bet adds to the jackpot. It's special because anyone can trigger it while playing. Some games require specific bets to be eligible for the jackpot. It’s a type of slots game that a player of any level can enjoy.

Progressive Jackpots were introduced by International Game Technology back in the late 1980s, in the slot machine called Megabucks. This allowed people to win millions in the jackpot!

If you want to find the most popular progressive jackpot slots, head over to

Standalone Progressive Slots

A standalone progressive jackpot grows only on one slot in the casino. It's not connected to other games and doesn't join a network. Each game has its own jackpot meter that goes up when people play. When you finish playing, the jackpot stays the same until someone else starts.

Some examples of standalone progressive slots might include:

🎰 Slot⚙️ Provider💰 RTP
Genie AlmightyPlayzido95.48%
The 5 DragonsAristocrat95.17%
Goddess RisingNovomatic95%
Martian Miner Infinity ReelsReelPlay96.06%
Mystic Fortune DeluxeHabanero96.71%

Networked Progressive Slots

Big jackpot slots, called network progressives, link jackpots across many casinos. When people play, a bit of their bet adds to the jackpot shown on all connected games. These slots grow their jackpot as players from different casinos play. Here are five examples of these slots:

🎰 Slot⚙️ Provider💰 RTP
Arabian NightsNetEnt95.2%
Gladiator JackpotPlaytech91.46%
MegaJackpots CleopatraIGT88.98%
Divine FortuneNetEnt96.59%
Joker MillionsYggdrasil Gaming94.3%

3D Slots

3D slots are advanced slot machine games with realistic 3D graphics that make it seem like the game is popping out of the screen. Players of any caliber can enjoy 3D slot games, with their intriguing visuals and accompanying sounds.

The story of 3D slots started when online casinos came about in the 70s, gaining popularity in the mid 90s. But it wasn't until the mid-2000s that better 3D graphics tech came along, especially with Betsoft Gaming leading the way with 3D slots like "The Slotfather" in 2009.

These games changed online slots by making them super immersive, with cool stories and new features. Since then, lots of developers have jumped in, making the games even better and sometimes even adding virtual reality and augmented reality stuff.

🎰 Slot⚙️ Provider💰 RTP
Jungle Jim El DoradoMicrogaming96.31%
Turning TotemsThunderkick96.1%
Vikings Go To HellYggdrasil96.1%
Flaming FoxRed Tiger Gaming96.11%

Fruit Slots

Fruit slots are old-style slot machines with pictures of fruits like cherries, lemons, oranges, and watermelons. They're simple to play and have bright colors. Fruit slots are perfect for beginners due to their simplicity, but player of any caliber can enjoy.

Fruit slots began in the late 1800s and early 1900s with the first slot machines. They were in bars and gave out candy as prizes. Later, they started giving out money instead of candy, but they kept the fruit symbols. Fruit slots became popular in casinos worldwide. With online gaming, fruit slots moved to the internet and people still enjoy playing them because they're simple and remind them of the past.

🎰 Slot⚙️ Provider💰 RTP
Fruit ShopNetEnt96.71%
Fruit WrapThunderkick97%
Fruit ManiaPlaytech95.8%
Fruit BonanzaPlay N Go93%
Mystery Reels MegawaysRed Tiger96.81%

AWP Slots

AWP slots, also known as fruit machines or pub slots, are like slot machines you find in pubs or arcades, especially in the UK. They're different from regular casino slots because they have extra games where you can use your skills to win. You might be able to push the reels or hold them still in these games.

AWP slots can have bonus trails and other features that make the game more interesting. They still have fruit symbols like cherries and lemons, but they're fancier than the old-style slots. The point of AWP slots is to give players fun and a chance to win prizes while mixing luck with player skill.

AWP slots started in the early 1900s in the UK. They were like games you could play in pubs and arcades, but not for gambling. At first, you could win things like chewing gum instead of money.

Over time, they changed so you could win cash, but still play games. People liked them a lot in the UK, and they're still popular in places like pubs. They're fun to play because they mix luck and skill.

🎰 Slot⚙️ Provider💰 RTP
Rainbow RichesBarcrest95%
Book of Ra DeluxeNovomatic95%

🏆 Best Free Slots to Play in 2024 by Slot Type

In 2024, players can easily find all kinds of free slots to play, from simple fruit slots to ones with progressive jackpots. Whether you’re someone who focuses more on the graphics of the game, or just want to play the classic slot, there’s something for everybody available.

🎰 Slot ⚙️ Provider 💰 RTP
Guns N’ RosesNetEnt96.98%
Fortune's QuestGoldenGems Gaming96.17%
Jackpot GiantPlaytech94.22%
Berry BurstNetEnt96.56%

Best Classic Slot - Guns N’ Roses

NetEnt launched their classic Guns N’ Roses Video Slots™ game on the 22nd of January 2016. It features the band’s most popular music. NetEnt made this game to celebrate their 20th anniversary. There are 5 reels, three row slots with 20 paylines.

There is a special Bonus Wheel feature which gets triggered when the vinyl record symbol appears on the 1st, 3rd and 5th reels simultaneously. The bonus wheel then offers three types of bonus games, corresponding with the colors red, yellow and blue. Other special features include Legend Spins, which will give you three free spins, and the Appetite for Destruction Wild which provides a free spin along with an expanding wild.

There is also a multiplier you can get (between 4 to 10 times the bet) if you win at least 3 of a kind. Other than that you have the classic symbols and expanding wild symbol to create winning combinations with varying payouts.

Best Video Slot - Fortune's Quest

Fortune's Quest, a fun game from GoldenGems Gaming, came out in June 2023. You explore a magical world full of treasures and challenges. It's got great pictures, cool sounds, and exciting play. You can win with wild symbols, scatters, free spins, and a bonus round.

Just spin the reels and try to match symbols on the 5x3 grid. Wild symbols help you win, scatters give free spins, and bonus symbols start a special bonus round. The more symbols you match, the more you win.

Best Progressive Jackpot Slot - Jackpot Giant

Jackpot Giant is a slot game made by Playtech in 2014. Its theme is prehistoric. You spin 5 reels and try to match up symbols like volcanoes, rocks, and giants across 50 paylines.

Some unique features in the game include stacked symbols, a volcano bonus round, and scatter symbols that start the Giant Bonus round. The best part is the progressive jackpot, which you win if you get five wild symbols on the first payline.

Best 3D Slot - Flux

Flux, created by Thunderkick over a decade ago in 2014. It remains popular due to its high ratings and exciting features. With a 96.2% return rate and the potential to win up to 2562 times the initial bet, it's a straightforward yet engaging game where players match gem shapes on the board. It lacks a narrative or characters but appeals to many for its simplicity and lucrative rewards.

Best Fruit Slot - Berry Burst

NetEnt released Berry Burst on August 22nd, 2018. The game features vibrant fruit slots with a 5 x 3 reel setup and no paylines, instead paying out in clusters. Berry Burst has a decent RTP of 96.56% and medium volatility. 

🎲 Types of Slot Game Mechanics

Slot game mechanics refer to the different parts and features that make up how slot machines work. It includes important aspects like spinning reels, matching symbols, and winning combinations.

But nowadays, slot games are more complex, with bonus rounds, special symbols like wilds and scatters, and extra ways to win big prizes. Factors like how often you win (volatility), the average payout (RTP), and how much you can bet also affect how slot games play. 


Megaways is an exciting slot game mechanic that changes how many symbols show up on each spin. This means the ways you can win keep changing too. Usually, there are six reels, and each one can have between 2 to 7 symbols.

This can give you up to 117,649 ways to win! You win when you get matching symbols on reels next to each other from the left side to the right side. You'll find Megaways in lots of video slots online. It's not just for one kind of slot game, like progressive or classic slots. They also come in all sorts of themes, from fantasy to old-school fruit machines. 

Cluster Pays

Cluster Pays is a way you can create winning combinations in some slot games. Instead of lining up symbols in a row, you win when symbols touch each other in a group, like a cluster.

You need at least five matching symbols to make a cluster. When you win, the symbols disappear, and new ones fall down, giving you a chance to win again in the same spin. You'll see this feature a lot in newer online slot games that have cool themes and extra features, but not so much in older-style slot machines.

Cascading Reels

Cascading Reels, also called Tumbling Reels or Avalanche Feature, is a slot trick where when you win, the symbols that helped you win disappear. Then, new symbols drop down to fill the gaps. If these new symbols make you win again, the process happens again.

This can make you win multiple times in just one spin. It makes the game more fun and gives you better chances to win big. Cascading Reels are often seen in modern video slots, especially the ones with lots of action and cool features.

You can find them in different types of slots, but they're most common in online video slots with many paylines and bonus rounds.

Grid Play

Grid Play is a type of slot game where instead of spinning reels, you play on a grid. You win by matching symbols in rows or columns, like in puzzle games. When you win, the matching symbols disappear, and new ones fall in, giving you more chances to win again.

This style often includes cool features like Cluster Pays or Cascading Reels for extra fun. You mainly find Grid Play in newer online slots that have exciting gameplay and features, not so much in older or traditional slots.

💰 Slot Features

Slot features are different than game mechanics, they provide different ways to win in slot machines besides the spinning reels and lines you win on. They make the game more interesting for players and can help them win more money or get bonuses.

Some examples are special symbols like wild and scatter symbols, multipliers that increase your winnings, free spins, bonus games, and cascading reels. The big difference between regular slot stuff and slot features is that features add new and exciting things to the game, giving players more chances to win big or have fun in different ways than just spinning reels.

Free Spins

Free Spins are like a bonus in slot games. When you get them, you can spin the reels without using any more money. You usually get Free Spins by getting certain symbols or combinations on the reels.

While you're using Free Spins, you can win prizes without spending your own money. Sometimes, you even get extras like multipliers or special symbols that make winning easier.

Lots of people love Free Spins because they give you more chances to win without risking your own cash. Some famous slot games that have Free Spins are Starburst by NetEnt.

Bonus Rounds

Bonus rounds in slots are triggered in the game when you get certain symbols. They give players more chances to win or try something different from the regular spins.

Common bonus rounds are free spins, where you get to spin without paying, pick-and-win games, where you choose prizes, and wheel spins.

Examples of games with popular bonus rounds are "Book of Ra Deluxe," which gives free spins, "Wheel of Fortune," where you spin a wheel for bonus.

Wild Symbols

Wild symbols are icons in slot games that substitute for other symbols to form winning combinations. They enhance players' chances of winning by completing paylines or triggering bonus features.

These symbols come in various forms, such as expanding, sticky, or cascading wilds, each offering unique gameplay dynamics. Wild symbols are highly popular in slots due to their ability to boost excitement and payouts.

Examples of popular slots featuring wild symbols is ‘Book of Dead.’


Multipliers are a special feature in slot games that make your increase your winnings by multiplying them. They can be symbols in the game or come up when you get certain combinations. For instance, if you win with a 2x multiplier, your prize becomes twice as big.

Multipliers make the game more fun and give you a chance to win more money. Some famous slot games like Cleopatra use multipliers to keep players interested and give them the chance to win a lot.


In slot games, wilds are special symbols that replace others to help form winning combos, boosting chances of winning. They can be expanding, stacked, sticky, or shifting, adding fun and surprise to gameplay, often triggering bonuses. Wilds are loved by players and game makers alike for their thrill and enhancing winnings. Immortal Romance by Microgaming is a prime example of a popular slot featuring wilds.

Expanding WildsExpanding Wilds are special symbols in slot games. They grow to cover entire reels, making it easier to win. Regular Wilds swap for other symbols, but Expanding Wilds can create lots of wins at once. They spread out on the reels, giving you a better chance to win big.
Sticky WildsSticky Wilds are symbols in slot games that stay where they are for more spins, making it easier to win. While normal Wilds vanish after a spin, Sticky Wilds stay put on the reels for a while or until something specific happens, giving you more chances to win.
Walking WildsWalking Wilds are like special pictures in games with spinning pictures. Every time the pictures spin, these special ones move around the screen. They can make the game spin again for free and help you win more money. They're different from regular special pictures because they don't just stay in one place. They keep moving until they're not on the screen anymore. They make the game more exciting and give you more chances to win.

Gamble Feature

The Gamble Feature in slots is like a mini game. When you win, you can try to guess something simple, like the color of a card, to make your prize bigger. But if you guess wrong, you lose what you won. Some people like the excitement of this, while others prefer to keep their winnings safe. A famous slot game with this feature is "Book of Ra" by Novomatic.

⚙️ Slot Developers

Top online slot makers include Microgaming, known for Mega Moolah; NetEnt, famous for Gonzo's Quest; Playtech, liked for varied themes; Pragmatic Play, making fun games; and Yggdrasil, creating immersive experiences.


NetEnt, started in 1996, is a top gaming software maker. They're known for cool and fun games. Some famous ones are "Starburst," "Gonzo's Quest," and "Mega Fortune." NetEnt slots are liked for their awesome themes, great graphics, and fun gameplay. They have cool bonus rounds, unique stuff like Avalanche Reels, and high RTP (Return to Player) rates.

Play’n GO

Play’n GO is a famous company in online gaming. They started in 2005. They are known for making vibrant and captivating games. Play’n GO has many good slot games, table games, and special solutions. Some of their best games are Book of Dead, Reactoonz, and Fire Joker.

Play’n GO games stand out because they have interesting themes, great graphics, and fun gameplay. They also have bonus rounds that can give you a lot of money. The games are known to be fun to play, and also work well on phones.

Pragmatic Play

Pragmatic Play is a big player in making software for online games, especially betting ones. They started in 2015 and are known for coming up with new ideas. They have quite a few highly-reviewed games, like "Wolf Gold," "Great Rhino," and "Sweet Bonanza."

People really like Pragmatic Play's games because they're fun to play, look great, and have cool bonus stuff. The games cover different topics, from old civilizations to modern adventures, so there's something for everyone.


Microgaming started making online casino software in 1994. They're known for being a leader in the industry. They have a bunch of games, like "Mega Moolah," "Thunderstruck II," and "Immortal Romance." People like their games because they look good, are fun to play, and have different themes for everyone. Microgaming is most well-known for their progressive jackpot games.


Yggdrasil is a big deal in the gaming world. They started in 2013 and make really cool games like slots, table games, and lottery games. Some of their popular games are "Vikings Go Wild," "Valley of the Gods," and "Jungle Books." What makes their games special is the awesome graphics, fun gameplay, and cool features like "Splitz" and "Golden Bet."

📜 History of Slots

Slots form the foundation of online casino gambling given their popularity. However, slots are relatively new to casinos. Traditionally, people played table games like poker, blackjack, and roulette. Few people know the origin story of slots and their rise to popularity.

In the following part, we will cover the main events in the history of slots. We will look at their evolution from mechanical machines into video slots everyone knows and loves today. Read on for more!

Early Beginning - Invention of the First Slot Machine

The very first slot machine was invented by the Brookly-based Sittman and Pitt company in 1891. The apparatus featured five reels and 50 cards. The player’s goal was to create the best poker hand with these cards. After inserting a nickel, the reels would start spinning. It was up to the player to pull the lever and stop the reels. 

The first slot gained immense popularity across the world. These machines were usually installed at bars and saloons. Soon enough, it was practically impossible to find such an establishment without the slot machine. 

Charles Augustus Fey and Liberty Bell

In 1894, Charles August Fey introduced the first slot machine with an automatic payout mechanism. Fey had a background in electronics and engineering, which undoubtedly helped him solve the payout problems that other slot machines were experiencing. 

This novel idea was a significant improvement over previous machines. This created immense popularity around the Liberty Bell. The slot itself featured nine reels and five symbols: horseshoes, spades, diamonds, hearts, and a bell icon. Players could win anywhere from 5 to 50 cents. 

Mills Novelty Company and Fruit Slots

Herbert Mills, the founder of Mills Novelty Company, is another important person in the history of slots. At the time of Fey’s invention, Mills was already an established figure in the vending machine business. He quickly recognized the great potential behind Liberty Bell and acquired the rights to manufacture and distribute the machines. 

The entrepreneur decided to improve upon Fey’s design by creating several variations such as the Operator Bell and the Lionhead. Even though these machines had the same principle as Liberty Bell, they featured different symbols and aesthetic enhancements. Mills also introduced Cabinet designs, known for their luxury wood with intricate detailing. These cabinets enhanced the appeal of the slot machines.  

Due to the anti-gambling restrictions in the early 20th century, manufacturers had to explore alternative slot themes. That is how fruit symbols like cherries and plums were first introduced to replace traditional poker symbols. 

Benjamin “Bugsy” Siegel, a notorious American mobster and casino entrepreneur, played an important role in popularizing slot machines by Mills Novelty Company. Siegel installed a large number of Mills machines in his casinos and hotels in Las Vegas. This was a large milestone for Mills, which solidified its reputation as a leading slot manufacturer. 

First Electromechanical Slot Machines

The world's first electromechanical slot machine was created by Bally Technologies, the world-famous casino software company at that time. In 1963, they introduced the renowned Bally three-reel machine, which could be activated by pulling a mechanical lever. This led to the nickname “one-armed bandit,” a term still used today to refer to any slot machine. Moreover, it featured automatic payouts of up to 500 coins, which was unheard of back then. 

First Video Slot Machines

The development of audio and video technologies in the early '70s paved the way for the emergence of video slots. In 1976, the Fortune Coin Company created Fortune Coin, the first slot machine to utilize a 9-inch display from Sony to showcase symbols instead of traditional mechanical reels. Fortune Coin made its debut at the Hilton Hotel in Las Vegas. Following their great success, the company was acquired by IGT (International Game Technology) in 1978.

Introduction of Progressive Jackpots

It was IGT that brought another significant invention to the world of slots. In 1986, they introduced Megabucks, the world's first progressive jackpot slot. These machines didn't have fixed jackpots; instead, they were part of a network, and their jackpots could grow as more and more people placed their bets.

The machines in the US were connected via phone lines, and the prize pool started at $1 million. Consequently, the first progressive jackpot was won in Reno, Nevada, and amounted to almost $5 million.

First Online Slots

In the late '90s, slots rapidly gained popularity due to the emergence of online casinos. The classic three-reel slots with simple graphics and gameplay were replaced by games featuring elaborate themes, bonus rounds, and playing fields with multiple reels and pay lines.

Microgaming was the true pioneer of online slots. The company developed the revolutionary “Reel ‘Em In” and “Cash Splash”. The emergence of the internet also guaranteed unprecedented levels of connectivity between players from all around the world. 

Introduction of Themed Slots

As more and more slot developers emerged, iGaming companies felt the need to integrate unique themes and graphics that could set them apart. A lot of inspiration was taken from popular movies, TV series, and music. Besides that, mythological and ancient themes gained immense popularity.

iGaming giants such as IGT, Microgaming, and NetEnt have significantly contributed to the development of slot designs. For example, NetEnt released the legendary “Gonzo’s Quest”, while IGT focused on film sagas like “Star Wars” and “Indiana Jones”.

Future of Online Slots and Current Trends

It's safe to say that online slots have a promising future. With the development of AI models, virtual and augmented reality, and other technological innovations, slots are poised to become even more immersive. For now, players can enjoy live games like Monopoly and Lightning Roulette, where you directly interact with a human dealer. 

In general, it seems that the future of online slots has already arrived. For example, cryptocurrency integration is taken for granted among players nowadays. Besides that, most online slots can be enjoyed on the go from any mobile device. What remains to be seen is how providers will adapt to these innovations and what unique novelties will emerge in the market.

❓ Frequently Asked Questions

When should I start playing slots for real money?

To start playing slots for real money, players need to get acquainted with the rules of the chosen game, its paylines, and features, which can be done by playing slots for free at first.

Are there any free slots that pay real money?

It is quite rare for free slots to pay players real money.

Can you cash out free slot play?

No. You can't share Free Slot Play with others, turn it into money, and you have to use it on a slot machine before using other credits.

Can I have free casino slots?

Sure, you can play slots for free online. let you enjoy slot games without downloading or making an account. You can try out more than 2,700 free slot games right here on

Can you win money with free slot play?

Usually, when you get free credits or bonuses at a casino, you can't just turn them into real money right away. Casinos and providers give out free play to get people interested in their games. Some free slot machine apps let you win actual money. These apps make money from in-app purchases or ads. They might also let you earn virtual currency or tokens by playing the free slots.

Why do slots never pay out?

Slot machines might not pay out much because of something called the "house edge," which is like a fee the casino takes, usually around 5% of what you bet. 

So, if you bet €100, you can expect to lose €5 to the casino. In regular casinos, slot machines are set to give back 95% of the money they take in. 

For instance, if you put in €1, the machine is supposed to give you back 95 cents at some point. However, be careful in places like airports, bars, grocery stores, and service stations, as the machines there might only give back 50% to 75% of the money, making it less likely to win often.

Can I play online casino games for free?

Yes there are many casino games you can play online for free. We’ve talked about them above in our article.

Do online slots really pay?

Absolutely, you can win real money when playing slots online. When you use real money to bet on the games, the winnings you get are also for real. Plus, you might even win money by playing online slots with bonuses and extra spins that the casino gives you.

What is the luckiest slot machine to play?

Some top slots with high chances of winning at online casinos include Mega Joker (99% RTP), Codex of Fortune (98% RTP), Starmania (97.87% RTP), White Rabbit Megaways (97.72% RTP), Medusa Megaways (97.63% RTP), Secrets of Atlantis (97.07% RTP), Steam Tower (97.04% RTP), and Gorilla Go Wilder (97.04% RTP). These games are known for their good return rates, making them popular choices for players looking for a mix of fun and better odds.

Has anyone won big on online slots?

Reports show that online slot games have made many people millionaires. Some games have jackpots that keep growing until someone wins, and this jackpot can be worth millions. You might just need one lucky spin to win the whole big amount.

What is the easiest online casino game to win?

Slot games, baccarat, roulette, blackjack, and keno are some of the easiest casino games. You don't need much skill; it's mostly about luck. If you're new to gambling, try different games for beginners to find your favorite.

How do you know if a slot machine is hot?

You can't predict when a slot machine will hit the jackpot. They use a random number generator for each spin, making the results unpredictable.

How often do slot machines hit?

When you play casino games, it's hard to win. For slot machines, your chances of getting the biggest prize can be really low, like one in 5,000 to one in about 34 million, especially when you use the most coins.

What is the best online slot site?

If you're looking for online slots, you can find the best ones here, at

How can I increase my chances of winning on slot machines?

To boost your chances of winning at online slots, start by choosing the right slot machines that suit your preferences. Before placing real bets, practice in demo mode to get a feel for the game. Make the most of casino bonuses to increase your playing time. 

Remember to bet responsibly and consider using a slots strategy, such as levels betting or fixed percentage betting. If you're using the Martingale Betting System, set a limit to manage potential losses. Following these tips can enhance your online slot experience and potentially lead to more successful outcomes.

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