Slot Machine Simulator

This is a simulator of a Blazing 7s slot machine, using the actual PAR sheet from the manufacturer which specifies the symbols on each reel. There are no graphics, it just does a bunch of spins and tells you the results.

Discussion

Jackpot's portion of total return

In most slots I've seen, the jackpot comprises <1% of the total return. But Blazing 7s is tricky. Since the payback on the machine is 92.70% for three coins and 92.52% for two coins, you might conclude that the jackpot is only 0.18% points of the return. In reality, if you played three coins but there was no jackpot prize, the return would be reduced by 1.8% points. What's going on?

Well, if you look carefully at the paytable, you'll see that wins aren't multiplied for multiple coins on most wins, which is unusual for a slot. So, on wins up to Triple Bars, those wins contribute more to the total return on 2 coins, and less to the total return on 3 coins. That depresses the overall return fer 3 coins vs. 2. To make up for that, for all prizes higher than Triple Bars, there's a bonus for playing 3 coins. Usually there's a bonus for only the top jackpot, but on this slot the six top prizes contain a bonus for 3 coins. It might not look like there is because each prize, is doubled, but it shouldn't be, it should be only 50% higher. Take a look at the prize for three of Two Any 7's plus the Double symbol. If the prizes were distributed evenly across the number of coins, they would be 100, 200, and 300 for 1, 2, and 3 coins respectively. However, instead of 200 and 300 for two and three coins, it's 200 and 400. This bonus for six of the top prizes makes up for the fact that it's shortchanging 3-coin players on the lower pays, relative to the 1- and 2-coin players.

So how do we figure how much the jackpot comprises of the total return? We simply multiply the odds of getting the jackpot times the size of the jackpot, divided by the number of coins played. From reels 1 to 3, there are 2, 2, and 1 symbols respectively that can trigger the jackpot, among 72 stops total for each reel. So the odds of hitting the jackpot are 2/72 x 2/72 x 1/72, which is about 0.0000107. Multiplying that by the 5000-coin prize gives us 5.35% points, and dividing by 3 coins played gives us about 1.8% points.

So, without a jackpot, this game at three coins would be 92.7% - 1.8% = 90.9%. Ouch.

*Calculated Machine Return According to Symbol Frequency*

It's possible to estimate the payback of a machine by doing lots of spins, recording which symbols hit, and then using the frequency of the hit symbols to calculate the payback, but it takes lots of spins.  Assuming you could record 800 spins per hour and played for a full week (40 hours), then here are the results for the Blazing 7s slot, according to the sim I just ran, for 1000 attempts and 1 coin played:

• 50% chance of being off by within ±0.7% points
• 10% chance of being off by within ±1.4% points
• 1% chance of being off by within ± 2.2% points

When you run the spin simulation, the program does the same thing, recording which symbols landed on the payline, whether they were winning combinations or not, for each session.  Once a session is over, it uses that frequency data to calculate what the payback on the machine would be, assuming that the frequency we observed was in line with the expected frequency. That's where I got the figures I just mentioned. We do see that estimating the payback that way, rather than looking at the raw return, is much more accurate. Actual returns are in a much wider range than those predicted by using the symbol frequency.

Play slots online

I suggest you play something other than slots because slot odds are so bad.  You could also play online with fake money, because then it doesn't matter if you lose.  A good casino for free-play is Bovada, since it requires no download and no registration.  (If you see a registration box, you can close it and continue without registering.)  You can play with real money too, though I hope you won't (or at least won't bet more than you can comfortably afford to lose). (advertisement)

All my slot machine articles

• Slot machine basics.  How much it costs to play, how much you can win, expected loss, why they're a bad bet, why they're popular, how you can limit your losses, speed of play
• How to play slot machines
• Slot returns.  How much they pay back.
• The Randomness Principle.  Slots don't continually get looser and tighter as they're played.  They don't have to.
• How they work. Explains the randomness principle, and runs through the math to show how a game returns a particular payback percentage.  There's a companion page on Par sheets.
• Strategies. Tips for increasing your chances of winning, and saving money.
• Slot Jackpots.  Odds of hitting the jackpot, progressive jackpots, and other jackpot topics.
• Bonus Rounds (all about them)
• How to Beat Slot Machines, aka Advantage Play (AP).  It's not what you think: it's not easy, and for the most part, not lucrative.
• Slot Machine malfunctions. How and why slot machines screw up, causing players to think they've won the jackpot when they really haven't.
• Slot Machine Myths
• Slot Machine B.S.  Wrong info that's published elsewhere.
• Biggest Jackpots.  The largest slot and table game jackpot wins in Vegas.
• Skill-Based Slots.  The scoop on the new games in which your results aren't entirely determined by chance.
• Slot Machine Simulator.  I programmed an exact replica of the Blazing 7s slot (odds-wise).  Click it to play thousands of spins in one second and see how you do.
• Slot name Generator.  Randomly creates a slot machine name using common slot words.  Hilarious!