Understanding Odds Formats: Decimal, Fractional & American

The Three Odds Formats

Odds represent the probability of an outcome and determine your potential payout. There are three main formats used worldwide: Decimal (European), Fractional (British), and American (Moneyline). Understanding all three is essential for comparing odds across bookmakers.

Decimal Odds

Decimal odds are the most common format in Europe and on Tipstop. They represent the total return per unit staked, including your original stake. For example, odds of 2.50 mean you receive 2.50 EUR for every 1 EUR bet — a profit of 1.50 EUR. The calculation is simple: Payout = Stake x Odds.

Fractional Odds

Popular in the UK and Ireland, fractional odds show your profit relative to your stake. Odds of 3/2 mean you win 3 EUR profit for every 2 EUR staked. To convert fractional to decimal: divide the fraction and add 1. So 3/2 = 1.5 + 1 = 2.50 decimal.

American Odds

Used primarily in North America. Positive odds (+150) show how much profit you make on a 100 EUR bet. Negative odds (-200) show how much you need to bet to win 100 EUR profit. +150 means bet 100, win 150 profit. -200 means bet 200, win 100 profit.

Converting Between Formats

On Tipstop, you can switch between all three formats instantly in your settings. This helps you compare odds from bookmakers that use different formats without manual calculation.

Implied Probability

Every odds value implies a probability. For decimal odds: Probability = 1 / Odds x 100. So odds of 2.00 imply a 50% chance. Odds of 4.00 imply 25%. Understanding implied probability helps you identify value bets where the true probability is higher than what the odds suggest.