Bankroll & Bet Size Calculator
Size your bets with discipline: set your bankroll and unit size, or let Kelly find the optimal stake.
Smart bettors risk a small, consistent slice of their bankroll per bet. Set your total bankroll and a unit size to get your standard stake, or switch to Kelly to size a bet from the odds and your estimated win probability.
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Everything behind the numbers
What is a betting unit?
A unit is the standard amount you bet, expressed as a percentage of your bankroll, usually 1% to 3%. Betting in units instead of random dollar amounts keeps a cold streak from wiping you out and a hot streak from making you reckless. Set the unit once and your stakes scale with your bankroll.
How much of your bankroll to bet
A common guideline is 1 unit (1% to 2% of bankroll) on a standard play and up to 3 to 5 units on your highest-confidence spots. Flat-betting one unit per play is the simplest disciplined approach and the table above shows what each unit is worth at your bankroll.
The Kelly Criterion
Kelly sizes a bet from your edge: the bigger the gap between your estimated win probability and the price's implied probability, the more you stake. The formula is f = (decimal odds × probability − 1) / (decimal odds − 1). Because full Kelly is aggressive, many bettors use half-Kelly to cut variance. Switch to the Kelly tab above to compute it.
Protect your bankroll on BettorEdge
Better prices and lower fees mean your bankroll lasts longer and compounds faster. On BettorEdge you keep more of every win because there is no house vig eating your edge. Size smart, bet the better number, and play responsibly.
Frequently asked questions
How much of my bankroll should I bet per game?+
Most disciplined bettors risk 1% to 3% of their bankroll per bet (one unit), saving the larger sizes for their highest-confidence plays. Set your bankroll and unit size above to see the dollar amount.
What is a betting unit?+
A unit is your standard bet size as a percentage of your bankroll, typically 1% to 2%. Betting in units keeps your staking consistent and scales it to your bankroll.
What is the Kelly Criterion?+
Kelly is a formula for the optimal bet size based on your edge: f = (decimal odds × win probability − 1) / (decimal odds − 1). It maximizes long-term growth, though many bettors use half-Kelly to reduce swings. Use the Kelly tab above to calculate it.
Is the bankroll calculator free?+
Yes, it is free with no signup. Pair it with the better prices on BettorEdge to stretch your bankroll further.