Kelly Criterion & Position Sizer
Optimal bet sizing · Risk management · Growth simulation
Trade Statistics
Win Rate (%)
% of trades that are winners
Avg Win (R multiples)
e.g. 1.5 = win 1.5× your risk
Avg Loss (R multiples)
Usually 1.0 (1× your risk)
Kelly Fraction
Edge
37.50%
Positive edge
Expectancy
0.38R
Per trade average
Risk of Ruin
9.07%
Moderate — reduce size
Sizing Gauge
● Safe ● Optimal ● Over-bet
12.50%
Recommended position size
Kelly Variants
Full Kelly
Aggressive — high variance, optimal long-run growth
25.00%
$25,000
Half Kelly
Recommended — good growth with lower drawdowns
12.50%
$12,500
Quarter Kelly
Conservative — suboptimal growth, very safe
6.25%
$6,250
Your Fraction
50% of Kelly
12.50%
$12,500