Modern online casinos try to feature thousands of games. In this effort, they collaborate with hundreds of software providers to develop modern and classic online slots that players can enjoy at home or on the go, playing at a casino on their phones.
Some of the gambling sites we feature and recommend at kazinos.com have over 10,000 slots, a clear sign that the industry is shifting towards a quality-and-quantity era. This is why it’s important to understand more about the dominant casino games, how they work, and – of course – which are the best slots to play online.
Despite thousands of options, 10 slots online consistently rank among the top 10 worldwide in player preferences.
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Slots are the modern version of the One-Armed Bandits that appeared almost two centuries ago in US casinos. Since then, casinos have come a long way, first creating the so-called fruit machines, which then evolved into modern-day slots.
The word “slots” is used to describe pieces of software featuring nice graphics and sound whose operation is controlled by a Random Number Generator. A mathematical algorithm that guarantees the randomness of the result that appears on screen.
Slots project several symbol combinations on every spin, with predefined pay lines and bonus games that pay players according to a pay table. Most online casinos also offer free slots so that players can try the software and the mathematical algorithm before trying the real-money version.
Slots’ paylines are the predetermined ways customers can be paid for winning combinations. Each slot comes with a combination win book, sequences of symbols that, when they appear on screen, pay multipliers on the player’s bet.
Traditional slots and one-armed bandits had a single payline, while modern slots can have thousands of paylines, e.g. in games using the Megaways mechanism.
Similar to paylines, payout methods refer to the ways customers can cash out from their slot bets. Payouts, however, also include winnings from bonus games or other combinations that are not necessarily related to the paylines. Such payouts include, e.g., multiple scatter symbols on the screen or non-custodian bonus games.
Wild in slots is the modern equivalent of the Joker symbol. A symbol that works as a replacement for any symbol and creates more paylines. It’s very common in online slots to feature random “Wild Drops” that infuse more wild symbols onto the reels, thereby boosting the winning paylines.
Scatter symbols are the Holy Grail of modern casino players. These symbols, when they appear on screen in certain numbers (usually 3 or 4), trigger a slot bonus game; a special feature that boosts paylines, multipliers and – of course – player profits.
Modern slots are all about the bonus game. hence also for the scatter symbols. The vast majority of slots’ big or max wins are delivered through bonus games, which is also why most casino software providers have added a feature called “Buy Bonus” that allows customers to obtain 3 or 4 scatters at any time and enjoy more bonus games.
RTP stands for Return To Player, and it’s an algorithmic/mathematical parameter that defines the percentage of players’ winnings from a casino game for every 100 units bet.
Most slots have a return of between 96. This means that for every 100 units players, punters will get back 94% to 96.5% of that. These maths are set to deliver over 1 million spins per game. Which means players shouldn’t expect to get paid exactly 96.5% every time they gamble away $ 100.
The validity and fairness of these numbers are checked by independent authorities such as eCogra and iTech Labs. Two international organisations that need to guarantee every slot online, before it is even published on a casino page.
Performance variability, also known as volatility, is an important indicator of RTP for online slots. It’s that metric, figure, parameter, or algorithm (each software provider uses a different name) that defines whether a slot will pay more often but in smaller amounts or more rarely but in higher amounts.
Understanding volatility and how it works is key to establishing how to win online slots. While most players focus on RTP and gameplay, experienced and professional players also consider this parameter before choosing where to play.
Some slots are simple, and the paylines are easy to figure out. However, some online slots are built on more complex mechanisms, including lots of low-paying symbols, wilds, scatters, and thousands of paylines. It’s crucial to understand the basics of winning combinations and payouts, because otherwise, you might be playing blind.
Each slot game features many symbols. Low Symbols, high symbols, special symbols, scatters, wilds, etc. At the same time, online slots will allow players to choose the bet and the number of paylines, which, in turn, will determine how the icon combinations pay out.
Modern slots will pay any row, straight or diagonal that features the same icons. Low symbols usually pay an amount lower than or equal to the bet amount, while high symbols, wild and scatters will pay the bet amount or higher.
The icons are usually the same numbers you see on the card deck (A, J, Q, K, 10), but it’s becoming more widespread these days that new slots substitute classic symbols and icons with drawings and images that relate to the game story.
Calculating rewards for combinations on online slots has never been easier. There are several ways to figure them out, but most don’t require much effort:
Experienced players will always check and read about an online casino game before committing real money to gambling.
Scatters and Wilds bring unparalleled thrill to players’ eyes when they appear on the reels. Scatters are bonus game barriers; most slots online have a 3 or 4-scatter trigger mechanism for the bonus game. What is the bonus game? the absolute thrill! a separate stage within the slot itself, where multipliers go wild and low symbols usually disappear.
Wilds, on the other hand, are like Joker symbols. They replace any symbol on the reels, creating more paylines. In some games, there are wild drops, where the game randomly adds up to 100 more wild symbols to help players achieve greatness!
Progressive jackpots were a huge topic 10 or so years ago. They are still a big deal; however, some countries have banned them or restricted them at a national level.
But what are they? The progressive jackpot is the dream (or maybe the “wet dream”) of every casino player. It’s when an online slot sets aside a separate pot fed by a tiny amount from each spin played on the network. Once busted (random busting defined by the Random Number Generator), the lucky player will get the entire amount of the progressive jackpot.
Progressive jackpots have delivered the biggest casino jackpots in history, which, however, don’t pay out to free slots players.
Modern online slots can be less simple than traditional fruit machines, and the game itself might require some fine-tuning when trying for the first time.
After you have decided on all the above, you are ready to enter the world of free slots and the casino games in general.
Every casino in our list has been tested for licence, payout speed and game library.
Online slots have come a long way since the times that fruit machines and one-armed bandits dominated this segment of casino games. Modern rooms need to host games from various categories to compete for dominance in this demanding area.
The modern versions of the original best-selling games. Symbols are replaced with fruit icons, while wild and special symbols increase the number of paylines. Many fruit machines don’t offer bonus games and pay more for winning combinations.
Similar to fruit slots, most Joker slots won’t feature a bonus game and are mainly designed to offer excitement via a grid of increased paylines. Symbols are usually fruits or card deck icons, accompanied by wilds. Another game category that takes you back in time.
An innovation that changed the online games scenery almost a decade ago. Megaways slots offer a payline grid with thousands of winning combinations by adding a horizontal line at the top or bottom of the slot. Although a bestseller initially, they lost popularity due to lower margins. Created by Big Time Gaming, the patent is now used by various providers, including Playtech and NetEnt.
These are games that offer a jackpot, which can be won by achieving a jackpot combination or by getting a random jackpot symbol. Games’ jackpots are different from progressive network jackpots, which use a separate mechanism.
Progressive jackpots are associated with multiple games, usually from the same software provider. Players chip in a small sum every time they spin the game, with a lucky winner grinding one of the 3 or 4 big progressive jackpots. The algorithm randomly selects the winners and is not based on a winning combination.
When Book of Ra and Book of Dead first came out, no one expected that the Egyptian slots would become an instant hit among casino players. Currently, every game provider offers at least one “Book of” game, usually with a wild-expanding mechanism during the bonus round.
The innovation that saved the game for Amusnet and brought recognition to its games. Dice replace symbols, and the winning combinations depend on the number of dice on each reel. Most dice slots don’t include a bonus game, but Amusnet specifically has added a huge progressive jackpot to compensate for the lack of exciting bonus games.
Zeus, Poseidon, Age of the Gods and Minotaur are only a few legendary names that casino software providers use to tempt players to try their slots. Ancient Greek slots are famous for their bonus games, since Zeus thunders and Poseidon’s tridents can be part of the perfect scenery. Let’s not forget that Gates of Olympus, the most famous online slot in history, falls under this category.
Pragmatic Play’s Big Bass and its 25+ game saga are the most notorious of this list, with other software providers trying to develop their own fishing games. Hooks and nets appear on screen to “fish” prizes and bonuses, while Big Bass offers one of the greatest bonus games in history.
Crash games aren’t technically slots! But since they use an RNG to define winners and win amounts, we can add them to this list. Players are asked to predict the event timing while a multiplier runs on screen, offering a reward based on that exact multiplier. Confused? Well, you won’t be after your first try. Aviator from Spribe is a great start in this niche.
Regular and free slots feature a variety of bonuses and extra payment features. Innovation is limited these days, but now and then, a new idea rocks the online casino world.
The most common bonus feature, and by far the most popular, is the bonus game triggered when 3 or 4 scatter symbols appear on the screen. The game screen changes, and extra wilds and multipliers are added, significantly improving winning amounts.
Originally developed by Playtech, it’s currently featured in thousands of games from all providers. Hold and Win is based on the principle that games that include money balls will trigger a bonus game when 6 money balls appear on screen (sometimes the magic number can be 5 or 7). During the bonus game, the money balls accumulate to earn you huge winnings.
Jackpot Bonus games can be part of the standard bonus game or can be a standalone game. It’s usually a jackpot wheel that triggers randomly and helps players unlock one of the jackpots.
Similar to regular jackpots, with the difference that the amounts are different, usually higher, and part of the network jackpot.
Online casinos use several tools to lure you to their pages. Free Spins are one of players’ favourites since who doesn’t enjoy a few free rounds on the house? This casino bonus is usually part of the welcome package, with the free spins credited after the first deposit.
Lately, however, more and more casinos recruit no deposit free spins to make players’ registration even more tempting. These free spins are usually credited to use on specific games, with the vast majority of casinos offering them on Gates of Olympus and Sweet Bonanza.
The oldest and most traditional casino bonus. Players’ first deposit doubles, so the initial account balance is larger, allowing for more game time and potentially higher profits.
Unlike Free Spins, which can only be used on online slots, No Deposit Bonus (NBD) money can be used across any casino game. including roulette, blackjack and live game shows. Most casinos will offer NBD amounts between 10 and 20 units.
There are more than 150 casino game providers worldwide. However, 5 names occupy most of the top 10 positions in online casinos and offer most players’ favourite titles.
The undisputed king of slots online. The company that has changed the casino world like no other in the last decade. Gates of Olympus, Sugar Rush, Big Bass Bonanza and 500+ more games create the most legendary games portfolio in casino history. Pragmatic Play’s games usually feature high RTP and high volatility, paying out millions to players every year.
Book of Dead, Tome of Madness and Rise of Olympus are only a few of the legendary games created by Play’n Go. Yet another provider that invests heavily in High Volatility games, Play’n Go is a love-or-hate casino software developer.
One of the most controversial game providers. Slots aficionados swear that the games are rigged because they pay super rarely. However, when they pay….they pay! Le Pharaoh, Le Bandit, Le Zeus, Le Viking and many more extra super high volatility titles are waiting for you!
An innovator and early pioneer in the industry, Playtech still has loyal fans among casino players. Mostly known for the Age of the Gods and the Wizard Saga, has recently also focused on live dealers and live game shows.
Divine Fortune and Eternal Romance are the two all-time classics that brought NetEnt to the spotlight. In recent years, the company has been busy with merging its business with other providers (most notably Big Time Gaming and Evolution Gaming). Still, it remains committed to delivering medium Volatility and RTP slots.
You feeling lost when opening the slots page of a web-based casino? Well, you are not the only one! With the huge variety of such games and their 24/7 availability, it’s key to establish a mechanism that will help you choose the right game for ya.
Decide if your goal is to have fun or make money from playing slots online. Based on your goal, many different options make sense.
Try the free slots offered by most online casinos. It’s easier to check the game without risking money to verify that you enjoy the gameplay, the paylines, and the bonus game.
Navigate the list of games offered at each casino. Check what is Hot and Cold, what is new and popular. These categories help most players decide which game to open.
Go to the Info section of each slot and check the RTP and Volatility indexes. All games will display this on their info sheet.
Check the Bonus page of online casinos. Many games or game providers offer regular bonuses and free spins. For example, Amusnet has weekly slot tournaments, Pragmatic Play offers free spins on new games, and so on…
After reading and understanding slots online in a better way, it’s probably time to try playing yourself. Starting the journey in this world requires a few easy steps before you start testing games.
At the moment, there are more than 10,000 online casinos available worldwide to play. But not all of them are legit and safe. Selecting the right online casino for you isn’t always easy, but you have two options:
There are plenty of regulated and safe options for playing online slots. All you need to do is scroll to the bottom of a casino page and try to spot the license number, the regulating authority, the banking methods, etc
After figuring out what a safe and good online casino is, it’s time to open an account. This usually happens in 2 or 3 easy steps, which usually involve also verifying your email or phone number. Opening a casino account is free, and you can have as many online accounts as you might wish.
Most slot software providers will add a free money feature to their games. that allows players to live all the action and excitement and get to know the game before gambling away real money. Playing the game is completely free, but you still need to have an account with this casino and be signed in.
Make a deposit and use the welcome offers
As a new player, you have access to the welcome package of the online casino. On most occasions, your account will be credited with:
All casinos in our list will facilitate payments via cards, e-wallets and cryptocurrencies. These websies have also optimised their new polayer onboarding process, so that players can enjoy the action in less than a few minutes.
No, slots are not rigged when playing at a licensed online casino with an RNG algorithm that has been checked. Independent authorities and our staff have tested all casinos on our list for the fairness of their algorithms.
To increase your winning chances when playing slots, there is no strategy or trick because a Random Number Generator controls the algorithm. You can, however, control your bankroll management and change slots after each big win (over 10x of your bet).
Novomatic’s Immortal Romance and NetEnt’s Immortal Romance are considered the slots that pay the most. However, each casino has its own game collection, and you can check each game for RTP and Volatility.
You are losing at slots because you don’t leave when you should. People have a natural tendency to believe that slots that paid once will pay again. A good strategy is to leave each slot immediately after it pays a big win (10x of your bet).
Slots that combine high RTP and low to medium volatility are usually the best to make money. They pay more often but smaller amounts. Higher volatility slots are better suited for players who enjoy risks but also better rewards.
