Betting Odds Explained

Guide about betting odds and different ways of displaying them.

Written by Thomas Brown
Verified by BettingGuide team
Last updated 2024-02-21

Betting Odds Beginners Guide

If you are new to betting, learning how to understand, and find value in betting odds is a fundamental skill. In this guide, we will explain the three most common betting odds formats, and teach you how to work out the implied probability the betting odds represent. Betting sites use three different formats for betting odds, Decimal, Fractional, and American.

Decimal Betting Odds

Decimal betting odds are the default format for most online betting sites from Europe, and they are also our recommended format. The decimal odds represent the potential returns of the bet including the stake. Multiply the decimal odds by the amount you wish to bet to work out your potential return, and minus your stake to calculate the profit.

(Decimal odds x stake = returns - stake = profit)

Example: 2.50 x 100 = 350 - 100 = 250 profit

Fractional Betting Odds

Fractional betting odds are common in English speaking countries, with the United Kingdom using fractional odds as the default setting for most gambling sites. There is a simple way of understanding fractional betting odds.

Example: 3/1 = How much you win/how much you stake

For every $10 you stake, you will win $30, simple as that.

1/5 = Every $500 you stake, you will win $100.

American Betting Odds

American, or Moneyline odds, are shown as positive (+) or negative (-) numbers. The positive numbers show how much you might profit if you bet 100, and the negative number shows what you must stake to win 100. We do not recommend using the American style betting odds, but if you find it easier, most online betting sites offer the Moneyline odds format as an option.

Calculating Implied Probability

Odds reflect the implied probability of an event occurring, and it is important to know how to change the odds into a percentage to work out if there is value in the bet. We recommend using decimal odds, as you just need to divide 100 by the decimal odds to work out the percentage.

Example: 100/2.50 = 40%

Let's say, two football teams have seen both teams score in a combined average of 70% of their games.

If both teams to score was set at 2.50 (40%), there would be value in the odds offered compared to the 70% average.

Bookies With the Highest Betting Odds

Compare the bookies with the highest betting odds available. We independently test the betting margins (lower margins the better) and list the lowest margins below.

Betway betting margin - 4.35%

Read more

Unibet betting margin - 4.61%

Read more

William Hill betting margin - 4.76%

Read more

bet365 betting margin - 4.85%

Read more

LeoVegas betting margin - 4.92%

Read more

22Bet betting margin - 5.54%

Read more
888sport logo

888Sport betting margin - 6.18%

Read more

Sports Interaction betting margin - 7.62%

Read more