Convert between probability percentages, decimal odds, fractional odds, and American moneyline odds with payout estimates.
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The Odds Probability Calculator translates between international betting odds formats—American (+/- moneyline), Decimal (European), Fractional (UK)—and true implied mathematical probability. It calculates potential net profit and total returns for any given wager or investment.
P = \frac{1}{\text{Decimal}}, \quad \text{American (+): } P = \frac{100}{A + 100}, \quad \text{American (-): } P = \frac{|A|}{|A| + 100}Where Decimal odds represent total return per unit staked, and American moneyline indicates profit on a $100 stake (+) or amount needed to wager to win $100 (-).
Scenario: A sports team is listed at +150 American odds. Find the implied probability and profit on a $100 wager.
Implied Probability: P = 100 / (150 + 100) = 100 / 250 = 40.00%.
Decimal Odds: 1 / 0.40 = 2.50.
Fractional Odds: 150 / 100 = 3/2.
Profit on $100 stake: $100 × 1.50 = $150 profit ($250 total payout).
Decimal odds (e.g. 2.50) represent the total return for every $1 staked, including the original stake. They are standard across continental Europe, Canada, and Australia.
Plus odds (e.g. +200) show the profit made on a $100 bet ($200 profit). Minus odds (e.g. -150) show the amount you must wager to make $100 profit ($150 bet needed).
The vig (vigorish) is the bookmaker’s profit margin built into the odds. If two equal teams are listed at -110 each, their implied probabilities sum to 52.38% + 52.38% = 104.76%, giving the house a 4.76% edge.
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