Betting Odds Explained

Decimal odds

At decimal odds of 3.00, every £1 staked returns £3 in total if the bet wins. A £10 stake returns £30, including the £10 stake.

Fractional odds

Fractional odds of 5/2 mean £5 potential profit for every £2 staked. A £10 stake at 5/2 therefore produces £25 profit plus the £10 stake, for £35 total return.

Implied probability

Decimal odds of 2.00 imply 50%; 4.00 implies 25%. This is a mathematical conversion of the price, not proof of the true chance of the event.

Why probabilities can add above 100%

Bookmakers build a margin into a market. If you convert every selection's odds to implied probability and add them together, the total can exceed 100%. That excess is one way to see the market margin.