Risk of Ruin Calculator
Calculate the probability of depleting your bankroll before reaching your target profit
Input Parameters
Enter your bankroll details to calculate risk of ruin
Your total available gambling bankroll
Amount you bet per round
Casino advantage (Blackjack: ~0.5%, Roulette: 2.7%, Slots: 5-10%)
Amount you want to win before stopping
Risk Analysis
Risk of Ruin
0%
Probability of losing entire bankroll
Probability of Success
0%
Chance of hitting your target
Expected Outcome
$0.00
Average result after many sessions
Risk Level
-
Conservative, Moderate, or Risky
Understanding Risk of Ruin
What is Risk of Ruin?
Risk of Ruin (RoR) is the probability that you will lose your entire bankroll before achieving your profit target. This is a critical metric for any gambler to understand, as it quantifies the risk you're taking with your money management strategy.
The Formula
For games with a house edge, the Risk of Ruin can be approximated using the gambler's ruin formula:
RoR = ((q/p)^a - 1) / ((q/p)^(a+t) - 1)
Where: p = win probability, q = loss probability (1-p), a = bankroll in units, t = target profit in units
Key Factors Affecting Risk
- Bankroll Size: Larger bankroll = lower risk of ruin
- Bet Size: Smaller bets relative to bankroll = lower risk
- House Edge: Lower house edge = lower risk of ruin
- Target Profit: More modest goals = better success probability
Risk Levels
Low Risk
RoR below 5% - Conservative, sustainable gambling
Moderate Risk
RoR 5-25% - Acceptable risk for most recreational players
High Risk
RoR 25-50% - Risky, not recommended for serious players
Extreme Risk
RoR above 50% - Very likely to lose entire bankroll
Practical Tips
- Keep your bet size to 1-2% of your bankroll for low risk
- Set realistic profit targets (25-50% of bankroll)
- Choose games with lower house edge to improve your odds
- If RoR is above 25%, consider reducing bet size or target
- Remember: Due to house edge, long-term expected value is negative