There are several types of odds display and almost all the best football betting sites support several. The most popular are fractional odds, which show the ratio of winnings to bets. For example, 2/1 means that for one measure of stake you get two measures of winnings. You get £20 on top of a £10 bet, so a total of £30. Decimal odds are also popular - this is simply the multiplier of the stake. 3.00 odds is the same as 2/1: £10 x 3=£30.