Risk of ruin
Risk of ruin is the chance to lose your whole bankroll before you reach your goal – try your own numbers in the calculator above.
Bigger bets, fewer rounds
Example: a 200-chip bankroll and a +50 goal. With one-chip bets on red you need many spins, and every spin pays the house edge.
Flat betting one chip, only 0.1% of 20,000 sessions reach the goal within 300 spins, and the average result is -8.1 chips. Bigger bets end the session in fewer spins, so the edge has less time to work – but each losing spin takes a bigger part of your bankroll.
A fair game still ruins you with a big goal
- Fair game, no house edge: chance to reach the goal = bankroll ÷ (bankroll + goal).
- Goal equal to your bankroll: you reach the goal exactly as often as you go broke.
- Goal much bigger than your bankroll: you go broke far more often than you reach the goal.
In the calculator, raise the goal and leave everything else the same to see the risk of ruin climb.
The house edge tilts every game
- European roulette, red or black: 2.70%
- American roulette, red or black: 5.26%
- Craps pass line: 1.41%
A lower house edge lowers your risk of ruin, but no game here brings it below the fair-game number.
Set a loss limit you can afford
No betting system removes the house edge – the system tester shows this with real session runs. Systems like the Martingale trade many small wins for a rare large loss.
Pick an amount you can lose without trouble, treat it as your whole bankroll, and stop when it is gone.
Decide your loss limit before the first bet, not during a losing run.
Questions
What is risk of ruin in gambling?
Risk of ruin is the chance that you lose your whole bankroll before you reach the goal you set. It depends on your bankroll, bet size, goal and the house edge of the game.
How do you calculate risk of ruin?
In a fair game with no house edge, the chance to reach your goal is bankroll divided by (bankroll + goal), and the rest is the risk of ruin. With a house edge the risk is higher, so use the calculator above to get the number for your game.
Do bigger bets lower the risk of ruin?
Bigger bets relative to your bankroll mean fewer rounds, so the house edge has less time to work and the chance to reach a goal can go up. You still lose about 2.70% of every bet on average on a European wheel, and one losing run can end the session fast.
Can a betting system lower my risk of ruin?
No system changes the house edge. With default settings the Martingale lost the whole bankroll in 24.3% of sessions, and its average result was -11.2 chips.
What is good bankroll management for gambling?
Set a loss limit you can afford before you start and stop when you reach it. Choose games with a lower house edge, such as the craps pass line at 1.41% instead of American roulette at 5.26%.