Understand Slot Machines

• Slot machines may be computerized now, but they’re still the most popular gambling attraction at many casinos. While we can’t tell you how to improve your chances, we will explain how the machines are constructed and how to calculate the odds of winning.
• On this page, we explain how slot machines work and the essential playing concepts that can make a difference for your bankroll. Slots have evolved drastically from the first mechanical three-reel devices. These days, most slots are electronic, showing animated symbols on HD screens.
• Class II machines only mimic slots but they have bingo soul: the outcome of the game is determined by the draw of the bingo numbers, which are later translated into slot reel combinations. So, think of it this way – when you place a wager on such devices, you, actually, buy a lottery ticket.
• Understanding Slot Machine Payback Percentages. By John Grochowski. Every slot player has tough days when the wins aren’t coming. And many a player has had the same.

Playing slot machines is the most popular form of casino gambling in the world, and knowing how to win at the slots can be one of the most important things a gambler ever learns. Although today's slot machines have little in common with the original Liberty Bell made by Charles Fey in 1896, their shape, size and popularity certainly do.

Most amateur gamblers believe that if a slot machine hits the jackpot, then it immediately goes ‘cold’. They also believe the opposite is true; if a machine runs cold for hours, then it’s ‘due’ for a big payoff. But if you look inside modern slot machines, you learn the cold hard truth. Every single pull of the lever has equal odds of winning, and those odds are steep.

Since the earliest mechanical slot machines, gaming manufacturers have weighted the machines to tweak the odds. If you look closely at the reels of old machines, you’ll find many more blanks and low-scoring symbols than pots of gold, especially on the third or final reel. This creates the famous ‘near miss’ effect.

Modern slots have replaced the gears, cranks and stoppers with precision step motors and random number generators (RNG). When you pull the crank on a modern slot, a built-in RNG selects three numbers between one and 64. Each number corresponds to one of 22 spots on the three reels. The trick is that half of the numbers between one and 64 correspond to blank spots and only one random number matches the jackpot symbol. The odds of nailing the jackpot are 1/64 x 1/64 x 1/64 or one in 262,144.

The lever is just for show. Three internal step motors spin each reel and stop them precisely at the positions chosen by the RNG. Still feeling lucky?

Return vs payback

There is no such thing as a ‘loose’ or ‘tight’ slot machine. In modern casinos, slot machines are programmed to deliver a precise return percentage, somewhere around 95 per cent. That means 95 per cent of the money that goes into a slot machine is paid back out to the players and the casino keeps the rest.
But here’s where things get tricky. The return percentage is not the same as the payback, which is the actual amount of money you win or lose during each gambling session at a slot machine. If you sat down at a slot machine for eternity and pulled the lever an infinite amount of times, your payback percentage would be exactly 95 per cent. Likewise, in a casino full of gamblers, the collective machines will pay back roughly 95 per cent of the total money gambled during the course of a day.

Unfortunately, you are only one person and you don’t have infinite pulls. So your odds of winning are equally good or bad every pull. You could lose all day and that doesn’t mean the machine is rigged. And it doesn’t mean that the guy who wins the jackpot found the ‘loose’ machine. He just got very, very lucky.

Top 5 Facts: Gambling stats

1) Big jackpot, big odds

The odds of winning the jackpot on a ‘progressive’ slot machine like Megabucks is one in 50 million, although if you are that one you’re likely to become very rich.

2) ‘Easy’ money

68 per cent of people who gamble at Las Vegas play the slot machines most often. And there’s a large target market as nearly 90 per cent of visitors to Las Vegas gamble.

3) The house wins

In the United States, gaming was a $92 billion industry in 2007, double what it was a decade ago. And in the UK, there were 143 casinos as of 31 March 2009.

4) United States of Slots

Understanding Slot Machine Pay Tables

Even though Nevada is widely considered the gambling state, there are 37 US states with some form of legalised electronic gaming device like slot machines or video poker.

5) Vegas’ most wanted

The Nevada Gaming Commission maintains a list of 35 people who are not allowed in any casino or gambling establishment. Only one of them is a woman.

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Most people look at the vast array of casino slot machines and assume they are all alike. They see a handle, a coin slot, flashing lights and figure one is as good as another. However, in making this assumption, they fail to see a lot of valuable information to help determine if they should play a particular slot machine.

Surprisingly perhaps, machines aren't all the same. The best way to separate one from another is to learn how to “read” a machine by looking at the payout schedule on the front. Let’s see what information can be found on a typical slot machine.

Casinos here in the U.S. and abroad keep several types of slot machines in play at any given time. A few you'll most often see:

Multiplier: This machine has a payout for a certain symbol and the number of coins played multiplies it. If the machine pays 5 coins for three lemons when you play one coin, it would pay 10 for the second coin and 15 for three coins played. This machine does not penalize you for not playing maximum coins. If you plan to play only one coin at a time, this is the type of machine you should look for.

Bonus Multiplier: This machine operates like the multiplier but offers a bonus when you play maximum coins and hit the jackpot. Three 7’s may pay 1,000 for one coin, 2,000 for two coins and 10,000 for maximum coins. The central question is whether the bonus is worth playing the extra coin.

Multiple Payline: These machines have more than one line of play. Each coin activates a particular line. If you hit a winner on a line that is not activated, you will not receive anything. The older machines used to have three lines but the newer video slots can have up to nine lines.

Buy-a-Pay: These are the most misunderstood machines in the casino. Each coin activates a different payout. You need the maximum coins to receive the largest jackpot.

One example is the Sizzlin' 7s machines. This machine will pay on cherries, bars, and sevens. The sevens pay 1,000 coins. If you play one coin you collect only on the cherries. If you play two coins you collect on cherries and bars.

Three coins are required to collect on the Sizzlin' 7s. If you hit the jackpot with one coin in you will not win anything -- do not play this machine under any circumstances unless you are playing the maximum coins.

Understanding Slot Machine Payouts

Progressive Slots: The progressive slots take a certain percentage of the money played and add it to a pool for the top jackpot.

First and foremost, It is never wise to play a progressive machine with less than the maximum coins -- stories abound of people losing out on lesser progressive jackpots because of short coin play.

Some casinos link machines together within their own facility to offer mini-progressive jackpots.

Megabucks and Quarter Mania are examples of machines from several casinos linked together to offer 'life-changing jackpots'. It's important to keep in mind that payback percentage on lesser wins is lowered to allow for these jackpots.

All of the information you need is posted on the front of each slot machine. Before sitting down to play, taking a minute to “read” the machine will help make you more knowledgeable in determining which machines may be best suited for you.

Until next time, remember:
'Luck comes and goes...Knowledge Stays Forever.'