Suggest a tool

Tell us what tool you wish existed. We build one every week from real user requests.

Invest smarter.

Kelly Criterion Calculator

Find the optimal bet size from your edge and odds.

Result

Full Kelly

25%

Half Kelly

12.5%

Quarter Kelly

6.25%

About this tool

Type your win probability and the win:loss payoff ratio. Get the full Kelly %, half Kelly %, and the loss-avoidance quarter Kelly. The r/options and r/sportsbook classic.

Related tools

More investing you might find useful.

Position Size Calculator

Compute shares to buy from account size, risk %, and stop distance.

R-Multiple Calculator

Score a trade by its reward-to-risk multiple.

Stop-Loss / Take-Profit Calculator

Plan a stop and target by R-multiple and risk percent.

Other categories

Looking for something different? Browse the rest of the catalog.

Sponsored suggestions

Some links below are affiliate links. We may earn a commission if you purchase through them, at no extra cost to you.