Bankroll Management Calculator
Project how your betting bankroll grows over time given your win rate, average odds, and staking percentage. Use it to test whether your staking strategy is sustainable before risking real money.
About this calculator
Bankroll management determines how much to stake per bet to maximise long-run growth while minimising ruin risk. This calculator models projected bankroll using a compound growth formula: projected bankroll = initialBankroll × (1 + edge × stakePercentage / 100) ^ timeHorizon, where edge = (winRate / 100) × (averageOdds − 1) − (1 − winRate / 100). The edge term represents expected profit per unit staked — the difference between what winning bets return and what losing bets cost. The stakePercentage scales that edge into each betting period. Compounding over a timeHorizon of bets shows cumulative growth or decline. Crucially, a positive edge is required for growth; staking more aggressively with a negative edge accelerates losses, illustrating why disciplined bankroll management is essential to long-term profitability.
How to use
Example: initialBankroll = $1,000, winRate = 55%, averageOdds = 2.00, stakePercentage = 2%, timeHorizon = 200 bets. Step 1: Compute edge = (0.55 × 1.00) − (0.45 × 1.00) = 0.10 per unit. Step 2: Per-period growth factor = 1 + 0.10 × 0.02 = 1.002. Step 3: Projected bankroll = 1,000 × (1.002)^200 = 1,000 × 1.4918 ≈ $1,491.80. Step 4: Adjust stakePercentage up or down to see how aggressiveness affects the outcome. A lower stake reduces variance; a higher stake amplifies both gains and potential drawdowns.
Frequently asked questions
What staking percentage should a sports bettor use to avoid going broke?
Most professional bettors recommend staking between 1% and 5% of their bankroll per bet, with 2% being a common baseline for moderate-risk strategies. The mathematically optimal stake (Kelly Criterion) equals edge / (averageOdds − 1), but full Kelly is highly volatile and many bettors use a fractional Kelly of 25–50% to reduce variance. Staking too large a percentage relative to your edge dramatically increases the probability of ruin even with a positive expected value. Starting conservatively and scaling up as your edge is confirmed over a large sample is widely regarded as best practice.
How does win rate interact with average odds to determine bankroll growth?
Win rate and average odds together determine your edge — the expected profit per unit staked. A high win rate with short odds (e.g., 70% at 1.50) may produce a smaller edge than a lower win rate with longer odds (e.g., 35% at 3.00). The formula edge = winRate × (averageOdds − 1) − (1 − winRate) shows that both components must be balanced. Understanding this interaction prevents the common mistake of chasing a high win rate at odds so short that the edge is negligible or negative.
Why does compound growth matter for long-term bankroll projections?
Compound growth means each bet's stake is calculated as a percentage of the current bankroll rather than a fixed amount, so profits from previous bets are reinvested and themselves generate returns. Over hundreds of bets, even a modest positive edge produces exponential bankroll growth through compounding. Conversely, losses also compound, which is why a negative-edge strategy depletes a bankroll far faster than linear arithmetic suggests. Running projections over a realistic timeHorizon using this calculator helps bettors set achievable targets and understand the true impact of variance on their results.