How Online Slots Work


Online slots give players the chance to win some serious cash by playing the latest animated games. The beauty of online slots is that they come in dozens of shapes and sizes: you can gamble on classic 3-reel slot machine or take a shot at the latest 1,024-payline games.

Online, you’ll be able to enjoy bonus features like free spins and prize wheels. You can also take a shot at a massive progressive jackpot worth millions. But how do they work, and how can you be sure the games are fair? Let’s take a look at what goes on behind the scenes in a typical slot.

Playing An Online Slot For Real Money


Online slots are quick to play and require little skill. The idea is simple: hit a Spin button and watch as a set of vertical reels spin. The reels stop at random, and horizontal paylines line up symbols across the reels. If the symbols match from left to right (starting with Reel 1), you win; if they don’t, you lose your stake and it’s on to the next spin.

On a typical 5-reel video slot, a reel can contain 30 symbols (although most slots have about 8 or 9 possible symbols, each with their own payout). The better slots – those with a higher RTP (Return to Player percentage) – will stack their reels with bonus symbols. It’s the job of the canny slots player to hunt out the best value.

If you check the slot paytable, you’ll discover details on the possible symbols and all the jackpots. You’ll also find information on any bonus rounds, and the arrangement of all paylines in the game.

Typical Bets & Features In Online Slots


A standard 5-reel online slot may feature up to 1,000 paylines but 10-50 is more common. Payouts are generally made from left to right, so it’s good to avoid slots that don’t have high-paying symbols on the first reel. Some slots also pay right to left for added excitement.

Coins and Bets: Individual bets are placed before a spin using ‘coins’. A coin be any value, from 1p to £50, and players can sometimes change the number of coins on each spin. A ‘Max. Bet’ button is a shortcut to the biggest stake possible in the game.

Reels and Paylines: Reels run vertical alongside one another, and can contain over a dozen symbols. Paylines run horizontally across the reels. In some games, the reels switch places after a spin, or even flip 180 degrees to form a whole new set of game reels.

Bonus Symbols: The majority of symbols in an online slot will be regular icons that award varying payouts when you land 2, 3, 4, or 5 on a payline. Special symbols like Wilds can substitute for regular symbols to help complete paylines. Scatters are symbols that pay out wherever they land on the reel. They don’t need to be part of a valid winning line.

Bonus Features: Bonus rounds are generally triggered by landing three or more Scatters on the reels. Bonus features can include free spins, an instant win game where one of three symbols must be selected, or a second-screen bonus where players select from 12 hidden objects to reveal cash and other prizes.

Online Random Number Generators


Online video slots and land-based versions are similar in many ways: they have super-HD graphics, animated reels, and computerised software. There’s one difference with some land-based games, however: the RNG is mechanical rather than computerised.

So, what does an online RNG do? The Random Number Generator tells the reels where to come to a stop. The whole process is random and is decided as soon as you hit the ‘Spin’ button. Some slots have a ‘STOP’ button which stops the reels early. Don’t think that there’s any skill involved: the reels have been determined beforehand.

When the reels are spun, the RNG performs a series of algorithms which churns out a series of numbers. Each number relates to a stop on the reel. There will be one number for Reel 1, one for Reel 2, and so on.

Trusting Internet Slots Software


Online casinos employ the services of approved testing bodies to check their games for fairness. It’s often a condition of a gaming license to have games and slots regularly tested.

Firms are independent of the casino and perform in-depth tests of games, running thousands of mock games on slots to check their average payouts.

Respected auditing firms include eCOGRA and TST/GLi. You can often find auditing certificates in PDF format on the casino site itself. They will list all tested RTPs (Return to Player percentages) across the casino. That includes table games and video poker, not just online slots.