Free Odds Margin Calculator & Converter

Calculate a betting sites odds margin

The calculator above helps to work out the margin that a bookmaker charges you for placing a bet on a specific event. It works for two-way matches, 1X2 events and outright-markets.

Look for betting sites with low margins - A lower bookmaker margin means a higher payout for you. On the occasions when you’ve predicted and bet money on the outcome of an event.

Convert between odds formats - The calculator does not only calculate margins. It also translates your inputs and displays the odds in different formats. It describes outcomes in decimal odds (EU), fractional odds (UK), american odds (US) as well as percentage to win and implied odds.

Why is it important to calculate the odds margin / payout? - In the long run, the margins a bookmaker charges on a match or sports event will significantly impact your results.

Why is there a margin at all?

Sportbooks and betting sites make their revenue by adding a margin to their odds. It's what they make their money on, both to be able to provide you with their service, cover their costs and make a profit.

This means that when you actually win, you get paid a bit less than would’ve been fair. The odds are lower than the payout multiplier should be, based on the probability of a particular outcome.

Let's look at an example. Say a betting site is offering odds on a heads-up match (2 teams with similar chances to win, without any draw outcome) at 1.95 and 1.95. If the betting site paid out all wagered money they would offer odds at 2.0 and 2.0.

At odds priced at 1.95 vs 1.95, the bookmaker margin is 2.56% and the payout for each $100 is $97,44. 2.56% is a low margin. The industry standard for eSports odds margins is higher, usually above the ~4% line.

The formula behind odds margin calculation

(1/Odds option A) * 100 + (1/Odds option B) * 100 + … = Margin

Working out the bookmakers’ margin on a 2-way market

1/Decimal Odds option A) * 100 + (1/Decimal Odds option B) * 100 = Margin

Example: Lyon Gaming is playing Ascension Gaming in a competitive League of Legends game. The bookmaker is offering 1.7 on Lyon Gaming to win and 2.05 on Ascension Gaming. By inputting the odds into the formula below we can see that the betting site charges a margin of 7.6%.

1/1.7 * 100 + 1/2.05 * 100) = 107.6

How to work out the sportsbook margin on a 1X2 market

(1/Home Odds) *100 + (1/Away Odds) *100 + (1/Draw Odds) *100 = Margin

Example: Sweden is playing Germany in a friendly soccer game. A betting site providing odds on the game has Sweden to win for 4.2. The odds for a draw are set to 3.9 and if Germany wins the bettor receives a payout of 1.9 times their bet. Given the input above the formula reveals that the betting site has priced the market with a margin of 2.08%.

1/4.2 * 100 + 1/3.9 * 100 + 1/1.9 * 100 = 102.08

Visit our eSports odds page to read more about how odds work and discover which eSports betting sites offer the most competitive odds. Wikipedia also has an solid odds wiki.