Fractional Kelly Calculator
Explore what the Kelly Criterion implies for a given scenario. Enter a reference unit base, the market odds, and a model win probability to see the fraction the formula returns for those inputs. The output is a hypothetical illustration, not a recommendation, and it is only ever as reliable as the probability you supply.
For mathematical modeling and position-sizing analysis only. Not financial or wagering advice. EdgeSlate does not accept bets or handle funds.
Fractional Kelly Position-Sizing Calculator
Mathematical position-sizing calculator based on the Kelly Criterion. Enter a model win probability and market price (American odds) to calculate the model-market difference and a capped fractional-Kelly allocation for that hypothetical scenario. For mathematical modeling and position-sizing analysis only. Not financial or wagering advice. EdgeSlate does not accept bets or handle funds. (5% max.)
Your inputs
Calculated Fractional Allocation
EdgeSlate is a research and analytics product. This calculator holds no funds and does not provide financial advice or promise outcomes. Adults 21+ only. If sports-related risk causes stress or harm, pause and seek qualified support. Never risk more than you can afford to lose.
What is the Kelly Criterion?
The Kelly Criterion is a mathematical formula that returns a fractional allocation for a stated probability and price. In sports analytics, researchers use it to explore proportional allocation across hypothetical scenarios based on a reference unit base. The fraction the formula returns is only as reliable as the probability supplied.
Why use "Fractional" Kelly?
Full Kelly returns the theoretical maximum-growth fraction, but it is extremely volatile and assumes the supplied probability is perfectly accurate. Because sports models are inherently probabilistic and variance is high, disciplined researchers almost universally apply a fractional multiplier (typically 1/4 or 1/2 Kelly). This reduces variance and the risk of drawdown while preserving a proportional allocation framework.
How to use this calculator
- Reference unit base: Enter your total dedicated research reference unit base.
- Odds: Enter the market odds for the scenario (e.g. -110 or +150).
- Win Probability: Enter the model's stated probability for the scenario (this is where you need a model like EdgeSlate's).
- Risk Level: Choose your fractional multiplier. We recommend Conservative (1/4 Kelly) for most users.
EdgeSlate provides analytical research and probability-based projections. Sports outcomes remain uncertain, and historical results do not guarantee future performance.