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Kelly Criterion Calculator

Calculate the optimal bet size based on your edge and bankroll.

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Recommended Bet (Full Kelly): —
Kelly Fraction
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Enter odds, probability, and bankroll
Full Kelly Bet—
Half Kelly Bet—
Quarter Kelly Bet—

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Kelly Criterion Calculator

Finding a good bet is one job. Sizing it correctly is the other. A Kelly Criterion calculator helps with the second part.

Most bettors spend all their time trying to find edge and almost none figuring out how much of their bankroll should actually go on the wager. That is how solid numbers turn into reckless staking. The Kelly Criterion gives you a formula-based way to size a bet using your bankroll, the odds, and your estimate of the true win probability.

The idea is simple: bigger edge can justify a bigger stake, smaller edge calls for less, and no edge means no bet. A Kelly Criterion sports betting calculator helps you apply that logic without guessing or betting by feel. Even if you do not use full Kelly, it is still a useful framework because it forces you to treat bankroll management like part of the edge, not an afterthought.

Prefer not to do this by hand? AVO's positive EV betting tool finds the +EV bets worth sizing with Kelly in the first place.

Frequently Asked Questions

What is the Kelly Criterion?

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The Kelly Criterion is a bet sizing formula. It helps you decide how much of your bankroll to risk when you believe you have an edge.

That is the part a lot of bettors skip. They spend all their time trying to find value and almost none figuring out how much they should actually stake once they find it. Kelly gives you a framework for that. Bigger edge can justify a bigger bet. Smaller edge calls for a smaller one. No edge means no bet.

That is why the Kelly Criterion matters. It is not about picking winners. It is about protecting your bankroll while still pressing your advantage when the number is in your favor.

How is the Kelly Criterion calculated?

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The full Kelly Criterion formula uses your estimated win probability, the odds, and the payout on the wager. The point is to calculate the optimal fraction of bankroll to risk based on edge.

A simplified version often gets repeated as "double the win probability and subtract one," but that only works in even-money situations. In real betting markets, the actual formula matters because the payout is rarely that clean.

That is why a Kelly Criterion calculator is useful. It does the real math for you and gives you a stake size based on the price you are getting and the probability you believe is fair.

Who created the Kelly Criterion?

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The Kelly Criterion was developed by John L. Kelly Jr. He originally created it in a communications theory setting, not for sports betting.

Over time, the formula became popular in investing, gambling, and bankroll management because the underlying idea carries over well: if you have an edge, there is a mathematically sound way to size your position without being reckless.

That is why the formula stuck. It gives structure to something most people otherwise do emotionally.

Explore AVO's betting tools

These calculators show you the math. AVO's tools do the finding — scanning 70+ sportsbooks in real time so the opportunities come to you. Every tool below is included in the free plan (up to 3% ROI bets).

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