Sports All tools

Kelly Criterion Calculator

Size a stake from edge, odds, and bankroll (full and fractional Kelly).

Suggested stake

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Worked result from default inputs (server-side math).

Win probability	Decimal	Full Kelly f	Half Kelly f
55%	2.00	10.00%	5.00%

Educational maths only. Not betting advice. Confirm live odds and terms with the operator. 18+.

Should I bet full Kelly?

Full Kelly is aggressive and assumes accurate probabilities. Recreational players often use a fraction (for example ¼ Kelly) or skip Kelly entirely.

Convert American, decimal, and fractional odds with implied probability.

Turn odds into win probability and reverse probability into fair odds.

Check if a sports bet is +EV using your win probability and the odds.