Roulette is often called the “King of Casino Games” because of its glamour, but mathematically, it is a machine designed to slowly bleed your bankroll. The payouts (like 35:1 for a single number) are calculated as if there were no zeros on the wheel. But those green zeros (0 and 00) represent the casino’s guaranteed profit margin.
Our Roulette EV Calculator strips away the glamour and shows you the math. By selecting your wheel type and bet, you can instantly see the House Edge and your Expected Value (EV)—the exact amount of money you are mathematically destined to lose on every spin.
Roulette EV Calc
Expected Lossyou will lose approx $270 every 100 spins.
How to Use the Calculator
This tool helps you make smarter choices by highlighting the most expensive bets on the table. Here is how to use it:
- Select Wheel Type:
- European (Single 0): The standard for online play. It has 37 pockets.
- American (0 & 00): The standard in Vegas. It has 38 pockets. Note how the EV drops significantly when you switch to this mode.
- Select Bet Type: Choose from standard bets like Straight Up (1 number), Red/Black (Even Money), or Corner (4 numbers).
- Enter Wager Amount: Input how much you are betting per spin (e.g., $100).
- Analyze the Results:
- Win Probability: Your percentage chance of hitting the bet.
- Expected Value (EV): This is usually a negative number. It represents the “fee” you pay to play. For example, an EV of -$5.26 means you lose $5.26 on average for every $100 bet.
Related Tools: If you are trying to determine the optimal bet size to make your bankroll last, check the Kelly Criterion Calculator (though be warned, Kelly is risky in negative EV games). To see how long you can survive at the tables before going broke, use the Risk of Ruin Calculator.
Real-World Examples: The Cost of the “Double Zero”
Many players don’t realize that adding a single extra pocket (the 00) nearly doubles the cost of the game. Here is the math.
Example 1: The “Safe” Even Money Bet
You bet $100 on Red.
- European Wheel: You have a 48.6% chance to win. The House Edge is 2.70%. Your expected loss is $2.70 per spin.
- American Wheel: Because of the extra “00”, your win chance drops to 47.4%. The House Edge jumps to 5.26%. Your expected loss is $5.26 per spin.
- The Lesson: Playing American Roulette literally costs you twice as much as playing European Roulette.
Example 2: The Worst Bet in Roulette (The “Basket”)
On an American Wheel, you bet $100 on the “Five Number Bet” (covering 0, 00, 1, 2, 3).
- The Math: This is the only bet in standard roulette with a different House Edge.
- The Result: The House Edge spikes to 7.89%.
- The Lesson: This is known as the “Sucker Bet.” Never make this wager.
Example 3: Straight Up (The Jackpot Hunter)
You bet $10 on Number 17.
- The Payout: If you win, you get $350.
- The Probability: You will only win 1 in 37 times (European).
- The EV: Despite the high potential payout, the EV remains -$0.27 (2.7% of $10). Whether you bet on one number or eighteen numbers, the casino takes the same percentage cut.
Frequently Asked Questions (FAQ)
Is there any betting system that beats Roulette?
Mathematically, no. Systems like the Martingale (doubling after a loss) can change the distribution of wins and losses (many small wins, one catastrophic loss), but they cannot change the House Edge. Every spin has a negative Expected Value, so no staking plan can turn that into a long-term profit.
Why is European Roulette better than American?
It comes down to the zeros. European Roulette has only one zero (0), resulting in a house edge of 2.70%. American Roulette adds a double zero (00), which increases the house edge to 5.26%. You should always choose European tables if available.
What is “La Partage” rule?
In some French/European roulette games, the “La Partage” rule applies to even-money bets (Red/Black). If the ball lands on Zero, you get half your bet back instead of losing it all. This cuts the House Edge in half, down to just 1.35%, making it the best possible game for players.