How Do Online Slots Work?

About Online Slot Machine Structure And RNG

Crispy graphics and high multipliers make the visible part of an online slot. While the player can interact with the slot via control panel, he has no access to the slot’s “brains.” What’s hidden behind the control panel? Is there any possibility to affect the outcome of the game? Read on to find out!

What’s Inside Online Slots?

Today, no one remembers the very first mechanical and electromechanical slot machines. They are displayed in museums as rare historical exhibits. A modern slot machine is a computer program running on super powerful servers of the manufacturing company. The player operates the slot via graphic interface, while all major calculations take place on the remote server.

This is how the majority of one-armed bandits work. This approach has a number of advantages. Most importantly, online casinos cannot rig slot settings in their favor. This way, slot producers can rest assured that the slot will continue to have its original settings. Plus, casino software brands have more powerful technical capacities to ensure flawless slot operation even during peak hours.

Let’s sum it up. Advanced slots are nothing more than computer programs. As a player, you can manage a slot (change bets, select paylines, etc.) via graphic interface, i.e. control panel. At the same time, all data are sent to the server owned by the manufacturing company and processed there. Now let’s talk about the random number generator (RNG) which is responsible for the symbols you see on the reels.

About RNG

Random number generator is also a computer program that creates strings (combinations) of random digits. Also, this term can refer to a device designed to measure the parameters of physical processes, such as temperature and frequency of a processor. Based on the measured data, RNG calculates strings of random numbers.

All the information inside RNG is securely encrypted by advanced algorithms. This is why hacking a random number generator is basically impossible. To do that, you would need extremely powerful computing capacities.

Neither online casino, no gamblers can interfere with slot settings and change them in their favor. This is how RNG ensures a fair and transparent play process.


When it comes to online slots, return to player (RTP) percentage is a far more important parameter than number of reels, number of symbols, and size of multipliers. RTP shows what percentage of all wagers made on a specific slot will be returned to players. At the same time, a 95% RTP doesn’t mean that you’ll get back $95 on each $100 wagered. The trick is that RTP is an average parameter which is only valid in long term. The more spins (and therefore bets) you make, the closer you’ll arrive to RTP in terms of payouts.