Slot Machine Q & A / FAQ
We receive emails daily asking questions about slot machines. When it makes sense we create an article to tackle a question in-depth. When it doesn’t we list and answer them on this page. You’ll find more than 20 slot related questions and answers below.
What Kind of Questions Do You Accept?
Any! We generally stick to answers about real live games, but do accept the odd online question.
The list below is only a small sampling, but it does reflect some of the more popular questions readers have submitted. This includes questions relating to payback percentages, RNG, where and how to purchase a used slot machine, cheating and so on.
Frequently Asked Questions
- Is gambling on a slot machine really random?
- Can and do casinos change the payout on slot machines?
- What is the difference between a class 2 and class 3 slot?
- Do UK fruit slots follow the same payouts as American slots?
- Is there a secret to winning jackpots?
- Is it legal or illegal to own a used slot machine in the US?
- Which slot machines have better odds?
- What is the highest denomination of slot machine?
- Which casinos still have coin operated machines?
- Are slots a stupid thing to play at casinos?
- How do you win at slots in Las Vegas?
- Is there a ‘best’ time of the day to play slot machines?
- Can you play slots for real money on your iphone?
- How do you use a slot machine?
- What are slot machines?
- Can you cheat the RNG on slot machines?
- Does the amount of money I deposit influence the slot machine in any way?
- How can I build a slot machine?
- Can a blind person play at a slot machine?
- Are slot machines in Nevada looser than the ones in California?
- Is there a Tomb Raider Slot machine?
- What does volatility mean when talking about slot machines?
- How do you reset slot machines?
- If slot machines are random, how can casinos guarantee how much they payback?
- Why are slot machines so addictive?
- What is the relation between slot machines and the number 7?
- Why do professional gamblers avoid slot machines?
- How do I pick a slot machine in a Las Vegas casino?
- Who made the first slot machine?
- Where can I buy a used or refurbished slot machine?
- What is the profit margin for owners of slot machines?
Yes. Both virtual and physical slot machines use a random number generator (RNG). This is a computer-run program or algorithm that randomly chooses numbers. Each number is connected to a symbol. When that number / symbol is chosen, it (the reel) stops. 
There is no such thing as a slot machine being due to hit or having a payout cycle. There might be exceptions, but not at a legit casino. Casinos wouldn’t want that anyway – they make the most money when games are entirely random with no element of skill involved.
Can and do casinos change the payout on slot machines?
Based on my research that varies on the casino, jurisdiction, type of machine, etc. With the machine it sounds as simple as changing the weight on the reels or swapping out a chip. In one of these cases the casino could alter the payout. However, if the casinos do there is paperwork involved, which includes reporting the changes to gaming authorities. 
What is the difference between a class 2 and class 3 slot?
The key difference between the two classes is that a class 2 slot machine is connected to a centralized computer system that determines the outcome of each wager. Class 3 slot machines are considered traditional slots, like those you’d see in Las Vegas. They’re played and pay out independent from a computer system, and the player’s chances of winning are the same each spin.
Each state will have regulations that determine what class of slot machines casinos or other establishments are allowed to use. 
Do UK fruit slots follow the same payouts as American slots?
No. This excerpt from the Daily Mail says it all:
In the UK, manufacturers claim most machines are set at 95 per cent but many pay out less – as low as 70 per cent in certain pubs and at motorway service stations, where the odds are worst of all; the transient clientele will not be around long enough to realise what an ungenerous fellow their fruit machine is.
A row of them in the corner of a UK pub will often make a landlord more money than the beer sales. In the US, games must pay out no less than 75 per cent by law. In the UK, there is no minimum payout; simply an obligation to print somewhere the payout percentage. 
Is there a secret to winning jackpots?
No. See question #1. Slot machines are random, controlled by a random number generator (RNG). No matter what ‘experts’ or ebooks tell you, there is nothing you can do to control the outcome of a slot machine.
Is it legal or illegal to own a slot machine in the US?
Which slot machines have better odds?
According to the Wizard of Odds, the simpler machines have the best odds. According to his research playing in $25 denominations have the lowest casino win (highest return to players). That’s over the long run though, and doesn’t mean that playing in $25 denominations will pay any better than $10 or $.01 during your visit.
What is the highest denomination of slot machine?
Which casinos still have coin operated machines?
Are slots a stupid thing to play at casinos?
Depends. What is your plan, to make a profit or to have a good time? If you plan to make a profit then I would say yes. If you’re playing slots to have a good time (and you’re well aware that it’s pure luck) then not at all.
How do you win at slots in Las Vegas?
By getting lucky.
Is there a ‘best’ time of the day to play slot machines?
Can you play slots for real money on your iphone?
Yes. Many casinos offer mobile slots. One example is Drake. Another is Win Palace. We have a page explaining iOS slots here.
How do you use a slot machine?
Each machine will be different, but the general process will go like this:
- You deposit your coins or voucher.
- If you have a VIP card, you stick that into the machine.
- Choose how many credits / lines you want to play.
- Hit spin or pull the handle.
Online the process will be the same, except every action will be by pointing and clicking with your mouse.
What are slot machines?
A slot machine is machine with 3 or more reels that spin when a button is pushed. Players start the process by inserting coins, cash, tickets, vouchers, etc. into the machine and then pressing a button or pulling a handle. The objective of slot machines is to win money by matching symbols on each reel to create a (winning) combination.
Can you cheat the RNG on slot machines?
Does the amount of money I deposit influence the slot machine in any way?
I answered this question above. The different denominations can have different payout percentages. Based on the chart he provided, betting in increments of $25 provided the highest payout percentage to players (at about 96%). But like I said above, this percentage is based on the long term and is not indicative of what you will earn over an afternoon or weekend session.
How can I build a slot machine?
That depends. One question that comes to mind is, do you want to build a physical slot machine or virtual machine that you play on your computer or phone? And what type of slot machine do you want to make?
If you want to create a basic iphone app, you can go to Udemy and learn how in under 3 hours (according to their description). 
If you want to build a real slot machine, one that you could keep and use in your own home, you’ll need a number of parts and tools, and software if you want to build a video slot machine. For that I recommend contacting slot machine manufacturers for parts and guidance.
Can a blind person play at a slot machine?
Sure, but without someone helping them playing at a standard machine would be difficult. They’d be at risk for being taken advantage of too.
That said, in 1995 Edward B. Kaplan patented the idea for a slot machine with Braille.  The machine would vibrate if the player won and would payout when a player pressed the payout button (to lessen the chances of theft). 
Are slot machines in Nevada looser than the ones in California?
The slot machines have to payout a percentage, which is based on a range provided by each individual state and federal guidelines.
That said, California does not have to meet a minimum payback percentage, nor do they reveal the percentages they do pay back. In Nevada you’ll see as much as 99% paid back to players, which depends on where you play (the strip in Vegas is considered the tightest at about 94%).
Is there a Tomb Raider Slot machine?
What does volatility mean when talking about slot machines?
It refers to how often and how much you win during your sessions. Low volatility machines will pay out more often, but the payouts will be small (more often than not). Higher volatility slots pay out less often, but the high volatile slot machines payouts are bigger.
How do you reset slot machines?
If slot machines are random, how can casinos guarantee how much they payback?
Why are slot machines so addictive?
That depends. Gambling in general can be addictive. The thought of winning life changing money is motivating, as is chasing losses.
What is the relation between slot machines and the number 7?
Why do professional gamblers avoid slot machines?
Professional gamblers have to make a living (otherwise they wouldn’t be professionals). Since slots are 100% luck, there’s no way they can guarantee they’ll win anything, let alone enough to make a living.
How do I pick a slot machine in a Las Vegas casino?
Pick a slot machine that looks fun. When I got to Las Vegas I play the video slots that have bonus rounds, like the Quick Hit Slots (with the wife) or the Dark Knight. I prefer these because they’re more like video games. I remember the movies too, so the different icons and bonus rounds make sense.
Who made the first slot machine?
According to Wikipedia the first slot machine was created by Charles Fey. His machine was created either in 1887 or 1895, and it has five symbols – horseshoes, diamonds, spades, hearts and a liberty bell. The machine was known as Liberty Bell. 
Where can I buy a used or refurbished slot machine?
There are a number of companies that sell refurbished slot machines. Rocky Mountain Slots is one. Another is London Bridge Slots and Slot Machines Ltd. You should be able to find each company by performing a search on Google.
What is the profit margin for owners of slot machines?
Over the ‘long run’ the profit margin is between 1-25%. That’s based on the payback percentage that the casinos set the machines to. However, that doesn’t take into account overhead, employees, servers, VIPs, etc.
The margins can’t be bad though. Based on my research one casino in Las Vegas has an average ‘money in’ of $220 per machine.
Sources for this article
- VegasClick.com: How slot machines work
- WizardOfOdds.com: RNG
- Wikipedia.org: Slot machines
- DailyMail.co.uk: Taking £1 and giving 70p back: How the fruit machine is ripping off Britain
- EastSideCannery.com: Slots & Video Poker
- Wikipedia.org:Slot Machine Manufacturers
- Google.com Patents: Braille slot machine US 5522728 A
- FutilityCloset.com: Jackpot
- Wikipedia.org: Slot Machine History