Casinos love to offer “50 Free Spins” or “100 Super Spins” as a welcome bonus. On paper, this looks like free money. But experienced players know the truth: not all spins are created equal.
A set of spins on a low-volatility game like Starburst is a completely different asset class than spins on a high-variance monster like San Quentin. Our Free Spins EV Calculator goes beyond simple multiplication. It runs a Monte Carlo simulation to show you not just the “Average” result, but the Median result—the amount you are actually likely to win.
Free Spins EV & Variance
Monte Carlo SimBased on EV, you will need to wager roughly $0 to clear this bonus.
How to Use the Free Spins Calculator
This tool helps you audit casino bonuses to see if they are worth your time. Here is how to configure the simulation:
- Number of Free Spins: Enter the quantity offered (e.g., 50).
- Bet Size per Spin: Check the Terms & Conditions (T&C). Most free spins are played at the game’s minimum bet (usually $0.10 or $0.20), but “Super Spins” can be worth $1.00 or more.
- Game RTP (%): Enter the Return to Player percentage. Standard is 96.0% – 96.5%.
- Volatility: This is the most critical input.
- Low: Frequent small wins. Your result will be close to the EV.
- High/Extreme: Rare big wins. Your Median (P50) will likely be lower than the EV, meaning you will often win less than the average, but occasionally hit a jackpot.
- Wagering Requirement: If you have to wager your winnings 35x, enter “35”. The calculator will show how much volume you need to churn to clear the cash.
EV vs. Median: Why You Feel Like You’re Losing
Many players use a simple formula: Spins × Bet × RTP = Value. While this calculates the Mean (Average), it is misleading for high-volatility slots.
Example 1: The “Consistent” Bonus (Low Volatility)
You get 100 spins at $0.10 on a Low Variance game.
- Theoretical EV: $9.60.
- Median Win (P50): $9.00.
- Verdict: Safe. You will almost always walk away with $5-$15. Good for building a small bankroll.
Example 2: The “Jackpot” Bonus (Extreme Volatility)
You get 100 spins at $0.10 on a NoLimit City game.
- Theoretical EV: $9.60 (Same as above).
- Median Win (P50): $4.50.
- Analysis: Wait, why is the median so low? Because 90% of the simulation sessions end poorly. However, the top 1% of sessions hit for $500+. The “Average” is pulled up by those rare jackpots, but your likely outcome is disappointing.
Frequently Asked Questions (FAQ)
What is EV (Expected Value)?
EV is the theoretical average amount you would win if you played the bonus millions of times. It is calculated as: Total Bet Value × RTP. Positive EV (+EV) means the offer is mathematically profitable in the long run.
What does P10, P50, and P90 mean?
These are percentiles from our simulation:
- P10 (Unlucky): The bottom 10% of results. If you run bad, this is what you get.
- P50 (Median): The exact middle. You have a 50/50 chance of winning more or less than this amount.
- P90 (Lucky): The top 10% of results. This represents a “good run.”
How does the wagering requirement affect EV?
Wagering requirements act as a tax on your winnings. If you win $10 and have a 35x wager ($350 volume), you will lose a portion of that $10 while trying to complete the wagering (due to the house edge). If the wagering requirement is too high (e.g., 50x+), the bonus may become Negative EV.
Why is my “Median” win lower than the “EV”?
In high-volatility games, the payout distribution is skewed. A few massive wins (10,000x) inflate the average (EV). However, the vast majority of players will never see those wins. The Median represents the “typical” experience, which is usually lower than the mathematical average.