Card counting can give you a mathematical edge over the casino, but it cannot eliminate Variance. Even with a 1% advantage, a bad run of cards can wipe out an insufficient bankroll.
This specialized Blackjack Risk of Ruin Calculator uses the specific volatility of the game (Standard Deviation ~1.15) to tell you exactly how safe your bankroll is based on your bet size and edge.
How to Use the Calculator
To get an accurate result, you need to estimate your edge (Advantage).
- Bankroll ($): The total money dedicated to your Blackjack session or career.
- Bet Size ($): Your average unit size.
- Edge (%):
- Negative (-0.5%): Basic Strategy player. Risk of Ruin is 100% in the long run.
- Positive (+1.0%): Card Counter at a high True Count.
- Hands (Optional): If left blank, it calculates the risk for an infinite career. If filled, it calculates the risk for that specific session.
Example: The $10,000 Bankroll
You have $10,000 and you spread your bets to achieve a 1% Average Edge. You bet $100 per hand.
- Risk of Ruin: The calculator shows a risk of approx 13.5%.
- Verdict: Too risky for a pro. To get below 1% risk, you would need to lower your bet to ~$50 or increase your bankroll.
Frequently Asked Questions (FAQ)
What is the Standard Deviation of Blackjack?
For standard rules (3:2 Blackjack), the Standard Deviation is approximately 1.15 units per hand. This is much lower than Slots but higher than Baccarat. This value is hard-coded into our calculator for accuracy.
Why is my Risk of Ruin 100%?
If you entered a negative edge (e.g., -0.5%), the math of “Infinite Ruin” dictates that the casino will eventually take all your money. To survive, you must stop playing or find a way to flip the edge (card counting).