The Kelly Calculator
Given your win rate and your average win and loss, this is how much of your portfolio the math says to risk.
Hypothetical, for illustration only. Kelly assumes you know your true win probability and payout in advance — in practice both are estimates from a limited sample. Not financial advice.
52% of trades like this one work out
+20% of the amount risked, when it works
-20% of the amount risked, when it doesn't (your stoploss)
Half Kelly — a steadier starting point
10.0% of your portfolio
$1,000 on this trade
Full Kelly — the mathematical optimum, high variance
20.0% of your portfolio
$2,000 on this trade
Expected value per $1 risked
+0.8%
Expected growth rate of your portfolio per trade, at each possible position size. It rises, peaks at full Kelly, then falls, going negative if you risk enough on every trade like this.
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