Odds

There are three common methods for writing betting odds. Fractional odds are favoured by bookmakers in the UK and Ireland. Decimal odds are favoured in Europe, Australia and Canada whilst American odds (sometimes called Moneyline odds) are favoured in the US.

Fractional Odds

Odds of 4/1 mean that you will make £4 in winnings from a £1 stake. As you always get your stake back, the bettor will receive a total of £5 (£4 winnings + £1 stake). 4/1 is sometimes called ‘Four to one against’.

‘Four to one on’ refers to 1/4 and means that you will make 25p from every £1 stake.

‘Evens’ or ‘Even money’ means odds of 1/1 so you will make £1 from every £1 stake.

10/3 is known as ‘one hundred to thirty’ due to bookmaking tradition.

Decimal Odds

These reflect the amount of money paid out to the bettor by the company including stake. So decimal odds are equivalent to the decimal equivalent of fractional odds +1.

For example:
4/1 = 5 in decimal odds (4 divided by 1, plus 1)
1/1 = 2 in decimal odds (1 divided by 1, plus 1)
1/4 = 1.25 in decimal odds (1 divided by 4, plus 1)
5/2 = 3.5 in decimal odds (5 divided by 2, plus 1)

American Odds

American odds can be expressed as a positive or a negative figure.

If the figure is positive, the odds quote how much money will be won on a £100 wager. So 4/1 in fractional odds is +400 in American odds.

If the figure is negative, the odds are quoting how much money needs to be wagered to win £100. So 1/4 in fractional odds is -400 in American odds.

Evens is represented by either +100 or -100.

To convert American odds to Decimal odds depends on whether the American odds will be positive or negative.

If it’s positive, divide by 100 and add 1 (so +400 = 5 in Decimal odds).

If it’s negative, remove the minus sign, then instead of dividing by 100, you take 100 and divide it by the American amount, then you add 1 (-400 becomes 400. 100/400 = 0.25. 0.25 + 1 = 1.25 so -400 in Decimal odds is -1.25).

Conversion Table