How to Calculate Betting Payout
BettingCalculator.ca
Start with two numbers: your stake and the price. Converting that price to decimal odds gives a straightforward way to calculate a potential cash-stake return.
1. Convert the odds to decimal
Positive American +A: D = 1 + A/100. At +150, D = 2.50. Negative American −A: D = 1 + 100/|A|. At −110, D = 21/11, or approximately 1.9090909. Fractional N/M: D = 1 + N/M. At 5/2, D = 3.50.
American +100 and −100 both mean even money, equivalent to decimal 2.00 and fractional 1/1. American magnitudes below 100 and decimal odds at or below 1 are not accepted here.
2. Multiply to find the total payout
For stake S and decimal odds D, total payout = S × D. A $100 bet at +150 returns $250 if it wins. The word “payout” here includes the original cash stake. A losing single bet returns $0 under this basic model.
3. Calculate net profit independently
Net profit = S × (D − 1). With $100 at +150, profit is $150. At −110, a $100 stake returns approximately $190.91 and earns approximately $90.91. A $20 stake at 5/2 pays $70 and earns $50.
The calculator derives both payout and profit from precise values, rather than subtracting already rounded displayed amounts. It does not adjust one result to make a displayed equation appear exact.
4. Interpret ROI and probability
Winning-bet ROI = (D − 1) × 100%. At 2.50 it is 150%. This conditional return does not account for the chance of losing. Implied probability = 100/D, which is 40% at 2.50. This is an odds-derived percentage, not a prediction or a guarantee.
Precision, units and settlement
Finite input decimals are stored as exact rational numbers. Stake and odds input components support up to 12 decimal places; stakes and decimal odds are capped at 1 billion, American magnitudes at 1 billion and fractional components at 1 trillion. Unsupported inputs and excessive results are rejected.
Money is rounded independently to the nearest cent; an exact half cent rounds away from zero. For example, $0.005 displays as $0.01 and −$0.005 as −$0.01. Converted odds and percentages may be rounded for readability without changing calculations. All dollar amounts use the same units; there is no exchange-rate conversion.
Taxes, fees, pushes, voids, dead heats, deductions and operator-specific rounding are outside the model. A sportsbook’s confirmed settlement rules take precedence over a hypothetical calculation.
Promotional and each-way bets use different assumptions
A stake-not-returned free bet pays only its profit portion as cash. An each-way bet has two stakes and requires separate win and place calculations.