How to Use the Roulette Betting Strategy Calculator
Martingale, Fibonacci, and D'Alembert are the three most well-known roulette betting systems. Enter your base bet and how many losses in a row you want to be able to survive, and this calculator shows the total bankroll each system requires, the probability of hitting that losing streak, and the expected loss once the house edge is applied.
Martingale doubles your bet after every loss so a single win recovers everything lost so far. Recovery is fast, but required funds grow exponentially, making it the riskiest system. Fibonacci grows more gradually than Martingale, while D'Alembert only adds one unit per loss, making it the most conservative of the three.
No matter which system you choose, European roulette's house edge (about 2.7%) still applies. Reordering your bets cannot improve the long-run expected value — losses remain proportional to the total amount wagered, regardless of the pattern used to get there.
Frequently Asked Questions
No. Martingale, Fibonacci, and D'Alembert only change the order in which you bet — the underlying game odds (about 2.7% house edge on European roulette) stay the same, so long-run expected loss is identical.
Because the bet doubles after every loss. Just a handful of consecutive losses can make the required bankroll grow exponentially, quickly exceeding table limits or your available funds.