Odds converter (decimal, fractional, American)

Enter one price in any format to see the other formats and the implied probability straight away.

The three odds formats

• Decimal odds (2.50): the multiple you get back if it wins, stake included. A stake of 100 returns 250, a profit of 150. Common in continental Europe, Australia and Asia; every table and calculation on this site uses decimal odds.
• Fractional odds (6/4): profit written as a fraction of the stake. 6/4 means you win 6 for every 4 staked, so in decimal it is 1 + 6 ÷ 4 = 2.50. Used in the UK and Ireland.
• American odds (+150 / −120): the sign sets the meaning. +150 means a 100 stake wins 150 (decimal 1 + 150 ÷ 100 = 2.50); −120 means you stake 120 to win 100 (decimal 1 + 100 ÷ 120 ≈ 1.83).

Conversion formulas

• Fractional a/b → decimal = 1 + a ÷ b
• American +n → decimal = 1 + n ÷ 100; American −n → decimal = 1 + 100 ÷ n
• Decimal d → American = +(d − 1) × 100 when d is 2.00 or more, −100 ÷ (d − 1) below 2.00
• Implied probability = 1 ÷ decimal odds: 2.50 is 40%, 1.25 is 80%. Add up one bookmaker's implied probabilities for every outcome and the total is usually above 100% — the excess is the margin.

Customary fractions

Bookmakers do not write fractional odds with any fraction; they stick to a ladder of customary values (…, 5/4, 11/8, 6/4, 13/8, 7/4, 15/8, 2/1, 9/4, 5/2 …). So when a decimal price is turned into a fraction, the nearest value on that ladder is used, and the smaller one when two are equally close. For example, 3.74 is exactly 137/50, but the customary price is 11/4 (3.75). The same ladder is used when you switch the site's odds format to fractional (calculations always use the raw decimal value). If you type a fraction yourself, it is shown as entered, with the nearest customary value added when it is not on the ladder.

To compare many bookmakers in one table, see the odds tables; for the payout of several outcomes, use the payout & arbitrage calculator.

Examples

Odds and calculations are provided for information only.