SANDRACER.COM - Betting Overround Explained For Beginners

What Does "Betting Overround" Mean?

Beginners Question What is the overround?

Answer The overround, is the total percentage of all the odds, added together, in any individual betting market.

Common Usage The betting overround (or vigorish, juice, vig, overound, over-round) is the name punters and bookies have given to the profit margin odds compilers build into a gambling market. When you see, "book percentage 150%", that's a theoretical 50% drink for the house.

Formula A mathematical formula is used by bookmakers/layers to price up a betting market in the bookies favour, ie the house edge. All odds/prices have an equivalent probability percentage. Evens is 50%, 3/1 is 25%, 9/1 is 10% and so on.

So, when bookies write a book/market of odds for you to bet on and price up a betting event, they carefully build in a profit margin for themselves by using fractional mathematics.

You're not going to get from any single bookmaker, 2 evens shots and another price, in a race of 3, otherwise the bookie is actually gambling, just like a punter.

We call it arbitrage when the layers disagree who will win an event and the prices add up to an automatic winner for a gambler, who, if they spread thier bets around, mathematically, correctly, can guarantee a profit for themselves, whoever wins the race.

You may see a 2 horse race, with 2 evenly matched runners, priced up as such (if you are lucky enough to find a book as low as 9%).

Odds of horse 1: 5/6
Odds of horse 2: 5/6

Odds of 5/6 = a 54.55% probability. 54.55+54.55=109.1 This means the bookie should theoretically win 9.1% of the total wagers staked, if the same amount of money has been wagered by punters on each horse.

You can work out the overround, or easily price up your own football match, or even a 40 runner handicap like the Grand National, by writing down the odds percentage and adding up the total. Anything over 100% is the bookies projected profit, all things being equal.

Arbitrage If you find a betting market where the prices add up to less than 100%, that is called arbitrage. Arbitrage means 2 or more layers differ so much on their odds, that you can bet both sides of the event and collect a guaranteed profit, whatever the result.

Round Book If you find a 2 horse race, a snooker match maybe, where you can get evens on both participants winning, such a market is called a round book.

♠ Overround = Betting market in the layer's favour.
♠ Round Book = Betting market in no one's favour.
♠ Arbitrage = Betting market in the punters' favour.