Nowadays all slots machines are electronic and in case you are looking for a mechanical one, you must know it's not an easy task. The new generation of electronic machines are run by computer chips or CPUs. In the CPU a RNG or Random Number Generator is programmed.

Each time you pull the lever or push the button of a slots machine the RNG will randomly pick a number and the reels will spin that many times. No matter what type of machine you will play, regular or progressive, the RNG will ensure that you play a random and fair game. Take a look at the diagram presented below to understand this better:

Phase 1

The CPU in the slots machine is always working. No matter if someone is playing that machine or not, it is continuously generating random numbers.

Phase 2

The outcome of the game is decided immediately as you push the button or spin the lever.

When you pull the lever or push the button the CPU records the random numbers corresponding to each reel. Then the machine will spin the reels and they will stop depending on those random numbers. The machine already knows if you have won or not, even if you are not aware of it yet. As you are watching the reels spin, the machine already knows where they will stop and consequently if you will get a good payout, a jackpot or lose your bet.

Phase 3

The random numbers generated by the RNG must be somehow visually represented. That is why the CPU turns them into smaller numbers and these numbers correspond to the machine's reel positions. This varies to the software script the machine uses.

Phase 4

Your chances of getting a certain symbol depend on the number the RNG comes up with. For each position the RNG can come up with several numbers. The RNG may come up with as many as 10 numbers for a less favorable reel position. But it will come up with only 5 numbers for a more advantageous one. Your chances of getting a reel position with 10 numbers are twice as high as getting a position with 5 numbers.

The reels will stop according to the random number generated by the RNG. There are 22 possible stop positions for each reel. You will get some stops more often that other stops. Usually the stops that offer higher payouts have less chances of occurring.

The same principle applies to video slots and online slots. The only difference is that when playing video or online slots you do no actually get to see the reels spinning. You will see graphic representations of the reels, and not mechanical reels.



Because not many people understand how a slot machine actually works and what is the thing that makes her work they give birth to many myths about a slot machine. This page explained you in just a few steps how they work so you won't be one of the persons who make silly statements about slot machines.

If you want to get a better understanding on how a slot machine works, we offer you a more complex explanation on the 'soul' of an electronic slot machine - the mystical Random Number Generator.

Inside the slot machine is a microprocessor related to the one that you have in your computer with the difference that as a replacement for of running a program like Word or Excel, it runs a special program that generates numbers to correspond to the symbols on the reel of a slot machine. This special program is called the Random Number Generator (RNG).

The RNG generates a value between 0 and 4 billion (approx.number) that is then translated into a specific set of numbers to correspond to the symbols on the reels. The outcome of each spin is determined by the number selected by the RNG. This number is chosen when you hit the spin button or deposit a coin.

The RNG uses a formula known as an algorithm that is a series of instructions for generating the numbers. The scope of this is beyond most of our mathematical knowledge, but can be checked for accuracy. This is done by the casino control boards and other testing laboratories to make sure that the program performs as it should so the player will not be cheated.

Reel-type slot machines have a number of spaces on each reel that contain a symbol or blank. These is referred to as the physical stops. Most of the old mechanical machines had reels that could hold 20 symbols while the modern slots have reels with 22 physical stops. Microprocessing technology allows new slot machines to be able to accommodate a large number of virtual stops.