To place the most effective bets possible, itās vital to be able to evaluate the fairness and competitiveness of available markets. Understanding overround betting helps you do just tź¦hat. This simšple guide will teach you how to calculate the bookmakerās margin on any set of odds, ensuring youāre getting the best value on every bet you make.
What is Overround Betting?
To understand overround sports betting, we first needź¦ to wrap our heads around the overround. This is a profit margin built ā 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 ā of a particular outcome occurring. Therefore, all betting odds can be converted into a percentage of probability.
For instance, -500 implies an 8ź¦3.3% chance of that prediction being correct. +100 would be 50%, +200 is 33% and +10š“0000 is 1%, as just a few examples.
When you consider all markets, it would be logical that the final percentage would be 100%, as one of ź¦¬the possibilities occurring is certain.
However, because of the overround in bettinš½g, the final percentage of all probabilities will be above that amount.
For instance, letās say on a three-way moneyline Tšeam A is given odds with a converted probability percentage of 60%, Team B of 35% and the possibility of a draw is given 11%. That leaves us with an overall percentage of 106%, anād the 6% above 100% is the overround.
š¶ From a strategic point of view, you can think of overround betting as wagering with the bookmakerās margin in mind. The lower the percentage, the biggerź©µ the potential returns.
Alternatives to the overround
There as some betting sites, such as betting exchanges and pool betting sites, 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 arošund 2-5%. One easy way of thinking of the overround 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 percentages and added together, thatāź§s all you need to do ą½§to calculate the overround.
As an example, letās say in a two-way moneyline (meaning draws are excluded) betweenź¦¦ the Philadelphia 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
Thesāe may also come in fractional and decimal šodds, for instance +100 would 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.
Regardless of the odds, itās always easy to find the exact implied probability and overround, hereās an example of šhow 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 š number (50%ļæ½ļæ½). Do the same for the San Francisco Giants (54.64%).
Add these amounts together. So, 50% + 54.64% equals 104.64%. 4.64% is your overround. Thišs 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 providiš„š ng you with a decent return on your bets.
Witāh a few clicks, which with our betting overround calculator can take moments, you can simply determine the quality of your odds. Thatās incredibly valuable to any strategic bettor.
Generally speaking, an ošverround of under 110% is reasonable, and under 105% is exceptional.
It can also allow you to compare and utilize multiple bookāmakers for the best possible deal. On a basicļ·½ level, if you check the same odds across several sportsbooks, and one offers a smaller overround, then you know youāre getting the better deal.
Overround vs Vig
The vig and the overround are both ways of calculating the bookmakerās margin and the quality oš¼f theš odds youāre being offered.
Howeveź¦°r, the vig focuses on the profitability 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, meaning ifš¬ you bet $100,ļ·½ you get $100 either way.
But thatās withoš ·ut a profit margin. So, letās 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 pays $210 (original $110 bet plus $100 profit). The vig is the dź¦ifference in odds which creates the $10 profit.
Vig as a Percentage
Yoš„u can also understand the vig, just as you can the overš¼round, as an implied percentage of probability.
Using the above example, letās say you have been offered odds of -11ā0, and the true odds for this event would be +100. The implied probability for tšrue odds is 50%, and with vig is 52.38%. The difference between these numbers is 2.38%, and thatās your vig.
The overround for these markets would be 4.76%, and if we doubleš the vig across boš°th markets we also get 4.76%.
š In other words, they are different ways of measuring value, and ultimately provide the same conclusions.
Vig vs Overround Conclusion ā Latter More Practical for Most
The benefits of the vig are that it provides detailā¦ed information 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 coź¦mplicated. 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 ā You donāt need the vig to determine the quality of the odds on an individual market. Youš could simply find out the implied probability of that market and compare it to that of other top operators, the smaller the percentage, the better returns for you.
Overround in Different Types of Bets
The basic priš°nciples of overround betting remain the same regardless of the type of bet.
Whatās importaš nt in understanding how to work out overround betting for all markets is to determine which odds should count towards your calculations.
Essentiallź¦y, the odds should cover all possibilities.
On a basic level if we were looking at spršead betting on an American football 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 woš °uld require you to add up the possibilities of all participants as any of them could win.
ą¹ So, figure out which markets when put together will create a certain outcš§øome (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 thaną¹ excelšlent odds.
In just minutes if not moments, you can convert oddą¼ŗs, add thš em up and understand their quality with unmatched clarity. It really puts into perspective whether your wager is a worthwhile one, and if so, where best to make it.
šThere are many elements to an effective betting strategy, but few are as important as ensuring maximum value out of each wager. Understanding tš¦©he overround in betting is one of the most powerful ways of achieving just that.
FAQS
The overround is the bookmakerās šbuilt in profit margin, calculated as a percentage above 100% when all possible odds are converted into percentages and added together.
The sports betting overround for horse races is conceptually the same as any other sport. All the odds converted into percentages and added together to get a total above 100%š· representing the bookmakerās margin. The only dš ifference is there are often many more potential winners in a horse race than most other sporting events so thereās more to add up.
As an example, weāve looked at the markets on š¦©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 together it comes to 105.71%, so the overround is 5.71%.
The overround are included as part of the odds on virtually all sportsbooks. Thereās nš§othing you can do to remove them in any practical sense. The only thing you can do is use your calculations of theļ·½ overround to find the best value odds possible.
Yes. The addition of a bookmakerās margin into the odds, in other words the overround, is both legal and standard practice from sportsbooks. Overrouź¦°nd betting, where you convert oš dds and use your knowledge of the overround to assess and compare the quality of odds, is also entirely legal.
No. Betting exchangesā instead make their profits by adding a commission onto net winnings,š¦© typically between 2-5%.