Fractional Odds

Fractional odds are the traditional British format, expressing profit relative to stake as a fraction. 5/1 ("five to one") means a 1-unit stake wins 5 units profit, for a total return of 6. 1/2 ("two to one on") means a 2-unit stake wins 1 unit profit — an odds-on price reserved for strong favourites. To convert to decimal, divide the first number by the second and add one. Worked example: a price of 7/2 equals 7 ÷ 2 + 1 = 4.50 in decimal. A £20 stake at 7/2 wins £70 profit (a £90 return). The Implied Probability is the denominator over the sum of both numbers: 2 ÷ (7 + 2) = 2/9, or about 22.2%. Fractional odds matter because they remain standard in UK and Irish horse racing, on course and in many shops, so reading them fluently is essential there. The common mistake is misreading odds-on prices. 1/2 is not evens; it returns less than double your stake, because the favourite is expected to win more often than not. Anything where the first number is smaller than the second is odds-on. Most online books now default to decimal, but fractions persist in racing. Compare with Decimal Odds, American Odds and Implied Probability.