To place the most effective bets possible, it’s vital to be able to evaluate the fairness and competitiveness of avail𝔍able markets. Understanding overround betting helps you do just that. This simple guide will teach you how to calculate the bookmaker’s margin on any 🌸set of odds, ensuring you’re getting the best value on every bet you make.
What is Overround Betting?
To understand overround sports betting, we first need to wrap our💟 heads around the overround. This is a profit margin built into the odds. This can be calculated as a percentage above 100% when all implied probabilities are added together.
How it works is simple. Odds indicate the likelihood of a particular outcome occu꧋rring. Therefore, all b🐲etting odds can be converted into a percentage of probability.
For instance, -500 implies an 83.3% chance of that predi🐠ction being correct. +100 would be 50%, +200 is 33% and +100000 is 1%, as just a few examples.
When you consider all markets, it would be logical that the final percentage would be 100%, as oဣne of the possibilities occurring is certain.
However, because of the overr🎀ound in betting, the f𒅌inal percentage of all probabilities will be above that amount.
For instance, let’s say on a three-way moneyline Team A is given odds with a converted probability percentage of 60%, Team B of 35% and the po🌟ssibility of a draw is given 11%. That leaves us with an overall percentage of 106%, and the 6% above 100% is the overro🍷und.
From a strategic point of view, you can think of overround betting as wagering with the bookmaker’s margin in mind. The lower the percentage,🌃 the bigger the potential returns.
Alternatives to the overround
There as some betting sites, such as betting exchanges and pool betting site🌸s, which use a commission instead of an overround. The commission is added to the net winnings of the users who won their bets. This is typically around 2-5%. One easy way of thinking of the overroun♋d is a type of commission built into the odds themselves.
How to Calculate the Overround
Since the betting odds overround is simply odds converted into perc🧜entages and added together, that’s all you need to doꦰ to calculate the overround.
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As an example, let’s say in a two-way moneyline (meaning draws are excluded) between the Philadelphi🌞a Phillies and the San Francisco Giants, the latter come in as favorites at -120 and the former are slight underdogs with +100 odds.
Different odds formats
These may also co💛me in fractional and decimal odds, for instance +100 wou𝔍ld be 1/1 in fractional and 2.00 in decimal. -120 would be 5/6 in fractional and 1.83 in decimal. All of these represent the same implied probability and overround.
Reg﷽ardless of the odds, it’s always easy to find the exact implied probability and overround, here’s an example of how to work out overround betting.
Go to the odds converter calculator (which you can think of as a betting overround calculator) found on our US guide to betting odds
Type the odds for the Philadelphia Phillies (any format) into the calculator. Make a note of that number (50%). Do the same for the San Francisco G𒀰iants (54.64%).
Add these amounts together. So, 50% + 54.64% eqওuals 104.64%. 4.64% is your overround. This works the same for all markets.
How Important is the Overround in Betting?
The overround is fundamental to how most online sports betting works. For the betting sites, the betting market overround is about maintaining profitability. For you, overround betting is a way of checking your betting site is providin🌱g you with a decent return on your bets.
With a few clicks, whi﷽ch with our betting overround calculator can take moments, you can simply determine the quality of your odds. That’s incredibly valuable to an🐠y strategic bettor.
�� Generally speaking, an overround of u😼nder 110% is reasonable, and under 105% is exceptional.
It can also allow you to compare and utilize multiple bookmakers for t🌳he best possibleও deal. On a basic level, if you check the same odds across several sportsbooks, and one offers a smaller overround, then you know you’re getting the better deal.
Overround vs Vig
The vig and the overround are both ways of calculating the bookmaker’s margin and the quality of the odds you’re being off🌠ered.
However, the vig focuses on the profitab🅷ility of individual bets, while the overround considers all possible markets.
Vig as Profit
🍬 To understand the vig, imagine a two-way moneyline bet on two evenly matched teams. True odds would be plus +100 (50%) for both teams, meani💛ng if you bet $100, you get $100 either way.
But that’s without a profit margin. So, let’s say the bookmaker instead moves the odds of both teams to -110. In this scenario, if $110 is placed on both teams, the bookmaker collects $220 and pa🅠ys $210 (original $110 bet plus $100 profit). The vig is th🦩e difference in odds which creates the $10 profit.
Vig as a Percentage
You can also understand the vig, just as you can the overround, as an impl꧅ied percentage of probability.
Using t🅰he above example, let’s say you have been offered odds of -110, and the true odds for this event would be +100. The imꦐplied probability for true odds is 50%, and with vig is 52.38%. The difference between these numbers is 2.38%, and that’s your vig.
The overround for these markets would be 4.76%, and if we double the vig acr꧑ꦦoss both markets we also get 4.76%.
In other words, they are different ways of measuring value, and ultimately provide the same conꦆclusions.
Vig vs Overround Conclusion – Latter More Practical for Most
The benefits of the vig are that it provides detailed inꦇformation about the value of a single bet as opposed to all markets together.
However, working out the vig, which on more convoluted markets requires you to normalize the probabilities and then convert true probabilities back to odds, can be very complicated. The overround is much simpler, especially with a calculator 🐼and will be more suitable for most sports fans.
TIP:
Comparing the value of single bets using overround – You don’t need the vig to determine the quality of the odds on an individual market. You could simply find out the implied probability of that market and compare it to that of othe🅠r top operators, the smaller the percentage, the better returns for you.
Overround in Different Types of Bets
The basic principles of overround betting remain the same regardless of the type o🔥f bet.
What’s important in understand❀ing how to work out overround betting for all markets is to determine which odds should count towards your calculations.
Essentially, the odds should cover al✱l possibilities.
On a basic level if we were looking at spread betting on an American f𝓡ootball game, it would work just the same as a two-way moneyline bet. These bets may be different, but you only have two sets of odds, one of which must come true.
In another example, a horse race can have several possible winners and🍰 would require you to add up the possibilities of all participants 🌞as any of them could win.
So, figure out whꦇich markets when put toge꧃ther will create a certain outcome (barring the total abandonment of the event), convert, and add them together. The overround betting meaning always remains the same.
ThePuntersPage Final Say
Overround betting is an assurance that you never have🌠 to settle for anything less than excellent odds.
In just minutes if not moments, you c🔥an convert odds, add them up and understand their quality with unmatcꦓhed clarity. It really puts into perspective whether your wager is a worthwhile one, and if so, where best to make it.
There are many elements to an effective betting strategy, but few are as important as ensuring maximum value out of each wager. Un🎉derstanding the overround in betting is one of the most powerful ways of achieving just that.
FAQS
The overround is the bookmaker’s built in profit margin, calculated as a percentage above 100% when all possible odds are conveܫrted into perౠcentages and added together.
The sports betting overround for horse races is conceptually the same as any other sport. All the odds converted into percent♔ages and added together to get a total above 100% representing the bookmaker’s margin. The only difference is there are often many more potential winners in a horse race than most other sporting events so there’s more to add up.
As an example, we’ve looked at the markets ꧃on a boxing event between Raymond Ford and Nick Ball. Ford is given odds of -175 and Ball odds of +138. Converted into percentages, the former represents 63.69% probability and the latter 42.02% probability. Added t🙈ogether it comes to 105.71%, so the overround is 5.71%.
The overround are included as part of the odds on virtually all sportsbooks. There💟’s nothing you can do to remove them in any practical sense. The only thing you can do is use your calculations of the overround to find the best value odds possible.
Yes. The addition of a bookmaker’s margin into the odds, in other words the overround, is bo♍th legal and standard practiඣce from sportsbooks. Overround betting, where you convert odds and use your knowledge of the overround to assess and compare the quality of odds, is also entirely legal.
No. Bettin꧒g exchanges instead make their profits by adding a commission onto net winnings, typically between 2-5%.