Fixed Stake & Bet Sizing Calculator
Find the right stake for any bankroll using fixed risk percentage with optional Kelly adjustment.
How Bet Sizing Works
Bet sizing is arguably more important than bet selection. A bettor with a modest edge who sizes incorrectly will go broke. A bettor with a strong edge who over-bets will also go broke — just slower and more painfully. The math of bet sizing determines whether your edge translates into long-term profit or variance-induced ruin.
Fixed staking bets a constant percentage of your bankroll on every bet. It's simple, conservative, and effective. The two most common sizes: 1% (ultra-conservative, for high-variance sports) and 2–3% (professional standard). Going above 5% per bet exposes you to serious ruin risk even with a genuine edge.
Kelly staking bets proportionally to your edge. The full Kelly formula is mathematically optimal for maximizing long-run bankroll growth, but it requires precise probability estimates and tolerates extreme swings. In practice, professionals use half-Kelly or quarter-Kelly to reduce variance while preserving most of the growth benefit.
This calculator combines both approaches: enter your fixed risk percentage and optional Kelly fraction. The recommended stake is the safer of the two — Kelly when it's conservative, fixed when Kelly goes aggressive. This hybrid approach captures the upside of Kelly while keeping downside risk controlled.
The Sizing Formula
Fixed Stake = Bankroll × (Risk% / 100) Kelly Stake = Bankroll × Kelly_fraction Recommended = if Kelly > 0: min(Fixed, Kelly) else Fixed Max Bets = floor(Bankroll / Recommended)
"Max Bets" shows how many bets at the recommended stake before hypothetical ruin — a rough drawdown resilience metric. Higher is safer.
Common Staking Plans Compared
Bet the same % of bankroll every time. Simple to track, smooth variance. Best for beginners and bettors with less precise probability estimates. Target 1–3% per bet.
Optimal for bankroll growth given accurate probabilities. Full Kelly is aggressive — use half or quarter-Kelly in practice. Use the Kelly Calculator to derive your fraction.
Frequently Asked Questions
What % of bankroll should I bet per game?
Most professional bettors use 1–3% per bet. 1% is ultra-conservative (suited for high-variance plays). 2% is the standard. Anything above 5% exposes you to significant ruin risk over a sample of 200+ bets.
Should I use fixed staking or Kelly?
Fixed staking is safer and easier to execute. Kelly is mathematically superior if your probability estimates are accurate. In practice, use Kelly as a ceiling: bet fixed unless Kelly says bet less.
What does 'Max Bets at Stake' mean?
It shows how many consecutive bets at the recommended stake before your bankroll reaches zero (if all lost). It's a ruin resilience metric. 50+ is safe. Under 20 is dangerous.
Can I paste the Kelly fraction from your Kelly Calculator?
Yes — run the Kelly Calculator first, note the Kelly % output, then enter it here. The sizing calculator uses it as a ceiling to prevent over-betting.