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    Odds converter

    Convert between fractional, decimal, and American odds instantly. See implied probability for any odds.

    Implied probability: 16.67%

    Quick reference

    FractionalDecimalAmericanImplied Prob.
    1/101.10−100090.9%
    1/41.25−40080.0%
    1/21.50−20066.7%
    4/61.67−15060.0%
    1/1 (evens)2.00+10050.0%
    6/42.50+15040.0%
    2/13.00+20033.3%
    3/14.00+30025.0%
    5/16.00+50016.7%
    10/111.00+10009.1%
    20/121.00+20004.8%
    50/151.00+50001.9%
    100/1101.00+100001.0%

    Fractional odds

    The traditional UK format. 5/1 means you win £5 for every £1 staked. The number on the left is your profit; the number on the right is your stake. Commonly used in UK horse racing and high street bookmakers.

    Decimal odds

    The standard format in Europe and most online bookmakers. 6.00 means your total return is £6 for every £1 staked (£5 profit + £1 stake). Decimal odds always include your stake in the return, which makes them easier to calculate with.

    American odds

    Used primarily in the US. Positive odds (+500) show how much you win from a $100 stake. Negative odds (−200) show how much you need to stake to win $100. The switchover point is +100 / −100, which equals evens (1/1 or 2.00).

    How odds conversion works

    Fractional → Decimal

    Divide the first number by the second, then add 1. For example, 5/1 becomes (5 ÷ 1) + 1 = 6.00. For 11/4: (11 ÷ 4) + 1 = 3.75. The "+1" accounts for your returned stake.

    Decimal → American

    If decimal ≥ 2.00: American = +(decimal − 1) × 100. So 6.00 becomes +500. If decimal < 2.00: American = −100 ÷ (decimal − 1). So 1.50 becomes −200. The crossover at 2.00 equals evens (+100).

    Implied probability

    Implied probability = (1 ÷ decimal odds) × 100. At 4.00 decimal, the implied probability is 25%. Remember that bookmaker margins mean the implied probabilities across all outcomes in a market sum to more than 100% — the excess is the bookmaker's profit margin (overround).

    Frequently asked questions

    Divide the first number by the second, then add 1. For 5/1: (5 ÷ 1) + 1 = 6.00. For 11/4: (11 ÷ 4) + 1 = 3.75.