Kelly Criterion Calculator
🛠️ Tools & FeaturesThe Kelly Calculator answers the most important question in betting: "How much of my bankroll should I risk on this bet?"
The Concept (Super Simple)
Should you bet your entire bankroll? NO — you could still lose. Should you bet $1? That's too conservative — you're leaving money on the table.
Kelly says: Bet exactly 20% of your bankroll. That's the mathematically perfect amount to grow your money fastest without going broke. [/example]
What You'll See
The calculator shows three levels:
🟢 Quarter Kelly (safest): Bet $33 ← Recommended for most people 🟡 Half Kelly (moderate): Bet $67 🔴 Full Kelly (aggressive): Bet $133 [/example]
Which Should You Use?
- •Quarter Kelly — Best for most people. Low variance, steady growth. You won't have big swings.
- •Half Kelly — Good if you're confident in the edge estimate and can handle some losing streaks.
- •Full Kelly — Maximum growth rate but wild swings. Only for people with iron stomachs.
⚠️ Kelly assumes your edge estimate is perfectly accurate. Since our model is an estimate, Quarter Kelly is the safest choice. You can always bet more later as you build confidence in the signals.
Setting Your Bankroll
Go to Account > Default Bankroll and enter your total betting bankroll. This pre-fills the calculator on every game page so you don't have to type it each time.
Learn more about bankroll fundamentals in our Bankroll glossary entry, or explore the full Betting Calculators page for additional tools like odds conversion and hold calculation.