Kelly Criterion Calculator
Free Kelly Criterion calculator. Estimate the optimal fraction to risk per trade based on win rate and payoff—with fractional Kelly for safer real-world sizing.
Kelly Sizing
Kelly and fractional KellyKelly sizing (with safety in mind)
A Kelly Criterion calculator estimates an “optimal” fraction to risk based on win rate and payoff. In trading, many use fractional Kelly because full Kelly can be too aggressive when edge estimates are noisy.
- Use fractional Kelly for robustness (e.g., 0.25× to 0.50×).
- Update inputs only with sufficient sample size.
- Pair with risk-of-ruin to sanity-check survivability.
FAQs
It’s for traders who want consistent risk management. Use it to plan position size, stops, and targets before you enter so the math is clear.
Yes. The concepts apply to MT5/Forex-style pricing. Exact results depend on your broker’s contract specs, symbol settings, and account currency.
Log the plan (risk %, stop distance, target, and rationale) in your trading journal so you can review outcomes and refine your rules over time.
Full Kelly assumes your edge inputs are accurate. In real trading, edges drift and sample sizes are limited, so fractional Kelly is often safer.
Explore core features
Pair these tools with the journal, stats, replay, and dashboards to build a complete review loop.
Compare alternatives
If you’re comparing DayTradingCentral with other journaling and replay tools, use our comparison hub to evaluate workflows side-by-side.