Slot Machine Cheats: Do They Exist?

slot machine cheats

The idea of cheating or otherwise using some type of exploit at an online casino with slots is an idea that appeals to those who can see the value of a quick cash grab. There have been mostly isolated cases of ways that cheating at online and land-based slots has been done in the past, though most of those ways are guarded and thwarted in today’s casinos.

We’re going to walk you through a lot of the theory and practice behind cheating at these games, starting with the functionality of online slots and moving on to specific examples of times where cheating has occurred.

Understanding How Online Slots Actually Work

To have a foundation of understanding for how cheating in online slots could actually work on a fundamental level, you need to understand exactly how the random number generator works with an online slot to produce the symbols you see on the reels. This all starts with a computer program that randomly determines a number with a high degree of actual randomness so that there are no patterns that could allow someone to guess which numbers are going to come next.

Each of the reels of a slot actually consists of a virtual “strip” of symbols that come in a specific order. These “strips” will typically be thousands of symbols long, and each position on the strip is numbered starting with 1, 2, 3… all the way to the final spot. The random number generator determines a random position on each of the “strips” for each reel, and that’s how the symbols are determined on the actual reels.

This immediately brings us to our first potential cheat: One idea would be to use an online slot’s stop function to skillfully have the symbols come to a halt in winning positions. This idea does not work online because the positions of the reels are already determined, as described above, before you would have the opportunity to press the button to stop the reels. Along these lines, the stop button’s only function is to speed up the playing of the game since you’ll end up with the exact same symbols on the reels regardless of whether you use it or not.

Exploiting Bad Programming

The online casino industry has been around since the mid-1990s, and people have been trying to figure out how to exploit bad programming in Internet slots the entire time. From our explanation of how the slots actually work above, an easy way to exploit a programming error would be if you could predict which spots the RNG was going to pick, or if you could influence the RNG directly. This would allow you to either know if the next spin was going to be a winner or actually force the next spin to be a winner just depending on the nature of the exploit.

There has been a handful of cases, and we’re talking less than five that we have ever heard of, where someone was able to guess with a relatively high percentage of accuracy whether the next spin was going to be a win. The way to exploit that would be to wager using the minimum bet size on spins that you suspect to be losing and then to crank up the bet size to a much higher level on the spins that you think will be winners. It’s easy to see how your winnings would more than cover the cost of all of those low-stakes spins between payouts.

These types of exploits have been particularly rare throughout the history of the industry, and they are virtually unheard of now. Software companies protect against this sort of thing by limiting access to the RNG after it has been audited, having regular (often monthly) independent audits of the RNG, and having all games hosted on their own servers to prevent tampering and to prevent people gaining unauthorized access to the raw code for the actual games.

Bonus Balance Exploitation

There is one method for sort of getting one over on online casinos with online slots that has worked a bit relatively recently, but they are cracking down on it more and more. The idea is that with certain games, you can run up an in-game balance on some kind of bonus meter or other type of feature. You see this a lot with feature guarantees. The concept at play is that you would run up this feature as high as possible without actually triggering the feature itself on as many games as you could. You do this with a bonus balance from a promotion you had taken advantage of.

Afterwards, you play through the rest of the bonus as usual, typically in a high-risk way with other slots so that you end up either hitting some big wins or actually just going bust. Once you go bust, you could make a real money deposit that did not have a bonus or wagering requirements attached to it. From there, you’d go back around to all of the games with a feature guarantee bonus meter built up, trigger all of the features almost immediately upon playing (usually free spins), and run up a bunch of winnings. The idea from there is that you are free to cash out without being subject to wagering requirements.

We have to admit that this is a pretty slick idea, and we can’t say that we would have thought of it on our own. However, the fact of the matter is that all reputable software companies have caught on to this type of thing, and you’ll have a hard time making it work today.

Land-Based Slot Cheating

Because land-based slots have been around for over a decade, there have been more opportunities for players to try to figure out ways to cheat at them. One of the main differences between land-based games and online games is that you will often use actual currency, typically coins, in land-based titles. There are mechanisms in place to try to verify the payment that you’re making, and in turn, this leaves more systems vulnerable for exploitation.

Coin Manipulation

The oldest trick in the book with anything that accepts coins for payment is to drill a small hole in the edge of the coin, tie a string through it, and fish out your coin after it has been counted for payment in the machine. People started out trying this with slots originally decades ago, and there have been so many improvements since then that there’s virtually no reason to even try it at this point.

Other people used an idea called “coin shaving” to make coins slightly smaller by grinding away the edges. The idea is that players could hit a “sweet spot” with the size and weight of the coin where it would be verified as payment but then kicked out the change dispenser because the machine simultaneously thinks it doesn’t weigh enough. If you got it just right, you would be able to use the same coin to play over and over again and run up winnings. However, modern machines aren’t vulnerable to this type of attack.

Finally, you have another really simple exploit in the form of fake coins. If you’re good at making them, and you can figure out how to make them or get them for less than the value of the actual coin (which is tough enough as it is), then you could end up with a pretty strong edge. However, many systems these days use electronic means for payment, which renders this type of coin manipulation tactic obsolete.

Mechanical Manipulation

Coin manipulation techniques for land-based slots are all pretty basic ideas, and none of them are all that interesting in the grand scheme of things. Mechanical manipulation of the actual functioning of the slots, however, is extremely interesting because there are so many more moving parts and internal systems that can be tampered with to produce results.

The light wand is a really simple idea that plays on one of these mechanical systems. At the time, there was a light sensor used to count out the number of coins that was being paid on any given win. The coins rolling past would block a beam of light inside of the slot, and each dark moment would be counted by the hardware inside of the machine to count out the number of coins that had been issued after a winning combination was hit on the reels.

The light wand was basically a small, thin set of wires with a light on the end that would be inserted into a certain part of the game to mess up the sensor. The coins couldn’t block the light from all angles, and that means that the slot would continue paying out many more coins than it was supposed to until the wand was turned off and withdrawn from the slot. Other methods for counting the number of coins that have been paid have been devised since then to keep this from being something players can use today.

Other forms of circuit manipulation, especially messing with a machine’s ability to keep up with the number of coins it has paid out or when it’s supposed to actually pay out, have been used over time as well. They all rely on the same sort of ideas, but the exact implementation varies from machine to machine.


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Software Exploitation

Finally, we get down to exploiting the software used in land-based slots. This is pretty interesting as well because sometimes there are people actually involved in the programming of the slots and their random number generators who can then use that knowledge to cheat at the games.

The case of Ronald Dale Harris is probably the most well-known. He was a programmer who inserted secret code into a lot of slot games that was extremely difficult to spot. He made it so that inserting coins in a certain order with specific pauses between the coins would lead to a winning payout every single time. If he wouldn’t have been greedy and gotten caught, there’s probably no way anyone would have ever known. As it was, he had this going for several years before getting caught after generating suspicions after some pretty questionably high wins.

While Harris was able to exploit aspects of the programming of slots that he himself put into play, others have been able to find other ways of exploiting holes in software that they had nothing to do with. One well-known case was based on a bonus feature that would become buggy if the player changed the bet size immediately afterward.

For example, you could play at a very low level of stakes until the bonus feature happened. At the end of the feature, a screen would present itself giving you the total payout for your bonus as a multiple of your bet size. However, if you immediately changed your bet size to something else, it would pay out a multiple of that changed bet size instead. This means you could play for a minimum wager until the feature started, but then you could be paid as if you had been playing for the maximum bet size. It’s easy to see how this was exploited until game operators figured it out.

The Bottom Line on Cheating at Slots

At this stage in the industry, the opportunities to cheat at online or land-based slots are few and far between. The online slot software companies and land-based casino game developers put so much time and effort into testing their games and actively monitoring payouts that they will know very quickly after something goes wrong the very first time, and they’ll patch any exploitable aspects of the games before you have a chance to really rack up winnings from them. Overall, cheating at slots is fun to think about and read about, but it has very little practical application in today’s industry.