Betting Margins Explained


The ever-expanding world of online betting offers endless opportunity for bettors to handpick the best odds and bets from a wide array of offers.

Many bookmakers will claim to have the best-valued odds, but the burning question every tipster and punter is keeping their minds on is whether they will truly get the best deal for their money.

All of those who want to remain on top of things and always make sure they get the best odds possible need to make sure they understand how betting margins work.

What betting sites and bookies in general will do is adjusting the odds in order to attract bets from as many bettors as they can with a simple aim of securing a profit whatever the outcome may be.

The way they do this is by offering odds that often exceed the statistical probability of a chosen event, making sure they secure what is called a bookmaker’s margin. It is usually represented as the betting over-round or the market percentage with amounts over 100% and it is that difference between the actual value and the marketing value of a particular product – in this specific case a bet.

How do you calculate a betting margin?

If we are to bet on a match between Novak Djokovic and Andy Murray with Djokovic available at the betting odds of 1.65 and Murray standing at 2.35, the betting margin for this particular game will be:

(1/1)*100 + (1/2.35)*100 = 60.6 + 42.55 = 103.15%

This is close to 100%, so punters are getting a good deal, but the bookmaker has put in a 3.15% margin here, so if they have an even book, with the same amount of money placed on each player, their profit is 3.15% of the market.