Sportsbooks display pricing in three primary formats: decimal, fractional, and American. Decimal odds are standard internationally, fractional odds are traditional across UK markets, and American odds dominate domestic coverage across the NBA, NFL, MLB, and NHL. Because each format represents the exact same probability and payout structure, understanding how to convert between them allows bettors to compare market boards accurately regardless of the sportsbook's default setting.
Decimal odds represent the total return on a single unit wagered, accounting for both the original stake and the net profit. To convert a decimal price into fractional odds, subtract one from the decimal to isolate the profit and express the remainder as a simplified ratio over one. To convert decimal odds into American odds, values of two or higher become positive American numbers representing profit on a base stake, while values below two convert into negative American numbers indicating the stake required to return that base profit.
Fractional odds display profit relative to the stake, formatted with potential profit on the left and the required outlay on the right. Converting fractional odds into decimal format requires dividing the numerator by the denominator and adding one to include the return of the original stake. For American conversions, fractions where the numerator is larger than the denominator become positive figures, while fractions where the denominator is larger translate to negative American figures.
American odds rely on plus and minus symbols centered around a baseline stake. To convert positive American odds to decimal format, divide the number by the baseline amount and add one. For negative American odds, divide the baseline amount by the absolute value of the line and add one. Both types can then be reduced to fractional format by expressing the ratio of profit to stake in lowest terms.