Casino software

Everything you need to know about the software that powers the games you love to play.

The vast majority of online casinos do not develop their games in-house. Rather, they obtain a license to use a games platform from a third-party developer. Therefore, it is the software developer who designs games and (most importantly) makes sure they are fair.

The basics

Many of the top software brands are quite picky about which casinos are allowed to use their gaming platforms. However, casinos prefer to host games from popular, respected developers. As a result, you are likely to notice a lot of commonality between the catalogues of games on different websites. Most casinos will just apply a branded ‘skin’ to virtual games, while the same online slots games will crop up on various domains.

Despite this, not all software providers offer the same service. Some have more games, others older games, some power poker clients, others provide sports books. For this reason, many players have favourite software platforms, which can be an important factor for choosing an online casino.

In order to please as many punters as possible, major brands often obtain licenses from multiple software developers.

How does it work?

New players may not be aware that the game developer who made the game and the online casino where they play it are two separate entities. Indeed, while a few brands choose to host one or two game studios’ titles, most like to offer their players the broadest range possible. How does this all work?

Each casino will strike a deal with a game studio in order to be able to offer that studio’s games to its customers. Once a deal is reached, the casino will be able to host the studio’s software and allow its players access to those games. The studio retains full ownership and control of its games, and is responsible for keeping them running correctly.

Think of the online casino as a library, where people can access books (games) created by authors (game studios).

Exclusive games

In some cases, casinos might work with game developers to create exclusive games. These would not be available to other casinos, even if they host that studio’s other titles.

Exclusive games are usually branded, like Mr Green: Moonlight, which is based on the Mr Green mascot and includes the casino name in the title itself. LeoVegas also has some exclusive titles.

Casinos can also host games exclusively for a defined period. This means that the game studio will make a specific title available to one or two casinos exclusively for a set period of time before it becomes available throughout the studio’s network of partners. A slot can be exclusive for a week or two ahead of the general release or as long as several months. This all depends on the kind of agreement a casino has with the developer.

Untrustworthy game providers

Just like there are rogue casinos, there are also untrustworthy game providers. We don’t normally hear too much about the latter because players generally only come into contact with the casino side of things and not the game providers themselves. However, the two often go hand in hand.

Like online casinos, game providers must be vetted. More accurately, a game provider’s games must be audited to ensure that they are completely fair. This is done by testing the Random Number Generator software built into each game. If a game fails that test, a reputable game provider will go back to the drawing board to see how it can rectify the issue.

Unfortunately, not all game providers are reputable. Games that are not 100% fair can sometimes trickle into the market, mainly through sketchy casinos that don’t mind using faulty software to increase the edge they have on their players. Indeed, some casinos are deemed shady or even blacklisted because they use games made by untrustworthy studios.

As a player, it can be difficult to determine whether a game you are playing is legit or not. That requires some professional testing. The best thing to do is to avoid these games and the casinos that host them. Check out our guide on how to spot a rogue casino to learn the signs to watch out for.

Reliable software providers

The software developers listed below are known to be credible and honest, taking all necessary steps to ensure that players enjoy a secure gaming experience:

Betsoft Online Casinos

Despite forming in 1999, Betsoft are still considered the young pretenders trying to break the monopoly of the ‘big five’ casino software providers: Microgaming, Playtech, NetEnt, IGT and Cryptologic. Learn more about Betsoft here.

Top CryptoLogic Casinos

Cryptologic are a software application provider based in Dublin, Ireland. Learn more about Cryptologic here.

IGT Online Casinos

Before being incorporated by the Italian lottery company GTECH, IGT were a key player in the online gambling market. Learn more about them here.

Best Microgaming Casinos

Microgaming have acquired near-legendary status in the casino gaming market, having built over 700 unique software titles. Learn more the company here.

NetEnt Online Casinos

NetEnt (Net Entertainment) has gained a great reputation for creating the best-looking slot games on the market. Find out more here.

NextGen Gaming

NextGen (Next Generation) Gaming are a subsidiary of the Swedish company NYX, who have put together some great slots. Find out more here.


Novomatic are an Austrian-based software company that can trace its roots all the way back to 1980. Learn more about them here.


Playtech are best known for running the massive iPoker network, but they also power 500+ casino games. Learn more about them here.

Top RTG Online Casinos

RTG (Realtime Gaming) are an online gambling company who develop and maintain download-only casino-based software. Find out more here.


Rival have been around since 2005, and are famed for their range of ‘iSlots’ – interactive slots. Find out more here.


Yggdrasil Gaming – established in 2013 – are a relatively new player in the market but they’ve already won awards. Find out more here.

A history of casino software

The first online gambling software was developed by Microgaming in 1994 and supported a handful of free-to-play virtual table games and online slots. At the time, players had to purchase a CD-ROM to download all the software necessary to play and dial-up modems made the whole process extremely slow and clunky.

It was not until 1996 that the first money wager was placed at an online casino, following the establishment of the Kahnawake Gaming Commission to regulate and license online casinos. In 1997, Grand Virtual developed new gaming software that offered better, faster access to more players.

The introduction of Flash technology also resulted in a smoother, more sophisticated gambling experience. Flash did away with CD-ROMs in favour of a ‘plug-in,’ coinciding with the emergence of fast DSL internet connections.

Shortly afterwards in 1998, Microgaming launched the first linked jackpot for their Cash Splash online slot game. In that same year, Planet Poker established the first online poker client. By the end of 1998, just four years after the first casino software hit the market, over 700 real-money casinos were operating online.

When the Java platform hit the market, it totally revolutionised online gaming, allowing for instant, ‘in-browser’ play, without necessitating downloads. This also paved the way for mobile gaming, allowing gamblers to access their favourite games from a variety of smart devices.

Today, a multitude of gambling products, from virtual table games to live tables and sports books, are enjoyed by millions of online gamblers via a whole host of platforms.

Random Number Generation (RNG)

All virtual casino games use ‘random number generation’ to ensure fairness. However, the RNG designation is slightly misleading, as microprocessors are incapable of true random number generation. In fact, online casinos commonly utilise ‘Pseudo Random Number Generators (PRNGs),’ which use an algorithm to generate a long stream of numbers to produce outcomes that are entirely pre-determined, resulting in a set ‘pay-out percentage.’

The most widely used PRNG algorithm in online gambling is the Mersenne Twister. This algorithm was developed in 1997 by Makoto Matsumoto and Takuju Nishimura and can produce sequences of numbers that are 219937 digits long.

While this system would appear to be fool-proof, a crooked casino game could contain a piece of code that recognises when a player has won and deliberately display incorrect information. Say, putting the ball in the 7 slot rather than the neighbouring 29 in roulette.

A number of organisations, including eCOGRA, independently audit the pay-out percentages of games based on PRNGs. They determine whether the numbers are in line with published odds and inspect software and numeric sequences for any hint of cheating. It’s helpful for gamblers to understand what RNG means for casino players means since this software powers most, if not all, casino games.

Live games

A number of software developers have started providing access to live casino tables via the internet, using cameras and data-streaming technology.

Live gambling has proven extremely popular with players, due to the assurance of seeing physical cards, wheels and balls operating under tangible conditions. By contrast, many gamblers liken virtual games to ‘playing with invisible dice.’

In the case of live games, chance, gravity and mass replace random number generators. However, virtual software is still used to distribute winnings.

Some casinos provide auto-roulette games, which involve a live wheel, but no dealer. In this case, PRNG software is used to generate ‘randomised’ bursts of compressed air that control the momentum of the wheel and the cast of the ball.