Bankroll Management Calculator

What Is Bankroll Management?

Bankroll management is the discipline of allocating a dedicated fund for betting or poker, then staking a controlled proportion of that fund on each bet or game. It is arguably the single most important skill for any serious bettor or poker player — not because it guarantees profits, but because it prevents ruin. Even a bettor with a genuine edge will go broke if their stake sizes are too large relative to their bankroll, through variance alone.

A bankroll is your dedicated gambling fund — money you have set aside specifically for betting, separate from everyday finances. Good bankroll management means never staking so much on a single bet that a losing run wipes out your entire fund. It also means your stake sizes adapt as your bankroll grows or shrinks, ensuring that wins compound and losses are survivable.

Fixed Stake vs Percentage Staking

The two most common approaches for sports bettors are fixed staking and percentage staking. Fixed staking means betting the same amount on every bet regardless of bankroll size — £10 per bet whether your bankroll is £500 or £1,000. It is simple and predictable but does not compound gains or protect the bankroll dynamically. Percentage staking means betting a fixed proportion of your current bankroll on each bet — typically 1–3%. This method means your stakes grow as you win and shrink as you lose, providing natural protection against losing runs.

For most recreational sports bettors, 1–2% per bet is considered conservative and sustainable. Staking above 5% per bet carries significant bankroll depletion risk through normal variance, even with a positive expected value. Use our calculator to see how different stake percentages affect your bankroll over a sequence of wins and losses.

The Kelly Criterion Explained

The Kelly Criterion is a mathematical formula developed by John Kelly in 1956 that calculates the optimal stake size to maximise the long-term growth of a bankroll. It requires two inputs: the decimal odds of the bet and your own assessment of the true probability of winning. The formula is:

Kelly % = ((b × p) − q) ÷ b × 100
Where: b = decimal odds − 1, p = your win probability, q = 1 − p

The Kelly Criterion only recommends a stake when you have a genuine edge (expected value > 0). If the implied probability of the odds exceeds your own probability estimate, Kelly outputs a negative number, telling you not to bet. This is one of its most valuable properties — it enforces discipline on value assessment.

Full Kelly can be highly aggressive and produce large stake recommendations on high-confidence bets. Most professional bettors use Half Kelly or Quarter Kelly to reduce variance while still growing the bankroll efficiently. Our calculator supports all Kelly fractions.

Bankroll Management for Poker

Poker bankroll management follows similar principles to sports betting but uses “buy-ins” as the unit of measurement rather than stake percentages. A buy-in is the cost of entering a single cash game session or tournament. The recommended number of buy-ins varies significantly by game type due to the differences in variance:

• Cash games: 20 buy-ins minimum. Cash games have lower variance than tournaments, so a smaller bankroll relative to stakes is acceptable.
• Sit & Go tournaments (SNGs): 50 buy-ins recommended. Higher variance than cash games due to the winner-take-most prize structure.
• Multi-Table Tournaments (MTTs): 100 buy-ins recommended. MTTs have extreme variance — even the best players regularly go 50+ tournaments without a significant cash.
• Spin & Gos: 200+ buy-ins recommended. The jackpot-heavy prize structure produces enormous variance.

If you currently have fewer buy-ins than recommended, our calculator flags this and suggests a lower stake level. Moving down in stakes to protect your bankroll is always the correct long-term decision.

Setting Up Your Betting Bankroll

Before applying any staking system, establish a clear bankroll:

• Only use money you can afford to lose. A betting bankroll should be completely separate from living expenses, savings, and emergency funds.
• Set a stop-loss. Decide in advance the point at which you will stop betting and reassess — typically 50% drawdown from the peak bankroll.
• Track every bet. Accurate records allow you to measure your actual ROI, assess whether your edge is real, and adjust stake sizes appropriately.
• Reassess regularly. Recalculate your unit stake at least monthly to ensure it reflects your current bankroll size.

Responsible bankroll management is also a cornerstone of responsible gambling. Visit our responsible gambling page for further resources, including tools for setting deposit limits and self-exclusion if needed.