Online Betting / Betting Guide / What Is Overround in Betting & How Does it Work Online?

What Is Overround in Betting & How Does it Work Online?

Jim Knight
Senior Editor
Fact checked by: James Leeland
Publish Date: 06.03.2024

Where do bookmakers get their money from? This question must have crossed many punters’ minds, as we know that bookies pay winners and run operations with funds. Understanding what betting overround means and how it works will answer these questions.

While online betting platforms get some of their revenue from lost wagers, this isn’t enough to keep them running. Bookmakers ensure that they make money on every event that’s wagered on, regardless of the outcome. This way, they never run out of money to pay out winnings. Did you just ask how? Read on as Oddsportal experts answer this.

What is Overround in Betting and Why Does It Exist?

Overround in betting refers to the amount of profit a bookie stands to make on every bet placed. Online bookmakers need funds to cover the costs of their operations and other necessary payments. This makes it vital to have a margin that will generate money regardless of the result of the betting options.

Importance of Understanding Overround Meaning

Overround isn’t just useful for online bookmakers but also the punters. Knowing how to calculate overround betting odds provides information that will aid your betting adventure. For instance, the lower the overrounds, the smaller the bookmaker’s payout. Knowing how to calculate overround will help you identify bookies with a lower commission, which is exactly the kind of bookies with whom you will want to place most of your bets.

Various betting sites on our online betting guides list have different margins. You can find house margins as low as 2% on some sites and as high as 12% on others because they have different targets and operating costs.

How Do Overrounds Work?

Betting overround is the total probability of the odds attached to each betting market that an online bookmaker offers. While betting odds show the probability of an event happening, and the total should be 100%, it’s not always the case with bookmakers. Online betting sites add their margin to make a profit which makes overround greater than 100%.

For instance, a 3-way match result market for Lazio vs Napoli assigned 2.32, 3.21, and 3.59, for 1×2, respectively. Calculating the overround shows that the betting market has 102% instead of 100% [(1/2.32 + 1/3.21 + 1/3.59)*100 =102%].

The overround meaning and the calculation above reveals that overround shows the margin added to alter the original probability of a betting outcome. This is usually to make profits from wagers made by punters, making it vital to bookmakers.

Calculating Betting Overround

In this subsection of our guide to overround in betting, we’ll talk you through how to calculate the size of it in your preferred betting outcome. The formula is:

( 1 / 1st outcome odds ) + ( 1 / 2nd outcome odds)  + ( 1 / 3rd outcome odds) x 100.

This is essential to know the actual gain you’re making on your wager. The steps are as follows:

  1. First, calculate 1 divided by the first outcome odds, then 1 divided by the second outcome odds, and so forth. E.g. 1/2.32, 1/3.21, and 1/3.59 as in example sites earlier.
  2. Sum the results using the same example, (1/2.32) + (1/3.21) + (1/3.59) = 1.022.
  3. Multiply the result by 100: 1.022 x 100 = 102.2%. Your odds overround is approximately 102%.

Don’t want to do the math? Fortunately, there are tons of free calculators available that allow you to simply insert the odds of your fixture and calculate the house edge near instantly.

How to Reduce the House Edge in Betting

Punters can’t influence betting overround because it’s set by the bookmakers. Though, proper knowledge of the concept and its calculations, coupled with some strategies, can help you beat the bookmakers’ betting margins. Some tips are discussed as follows:

Use Odds Comparison Platforms

Odds comparison websites will aid in reducing betting margins since it makes it easier to choose betting sites. The platform compares odds from multiple bookmakers, quickly enabling you to avoid bookmakers with high margins and stakes and go for the lower ones.

This tip requires you to have multiple betting accounts since you’ll be comparing odds; there is no point in comparing odds with another platform if you have no real options to choose the best offer.

Focus on a Sport and Market

Since you’re trying to compare odds between betting sites, it’s best to focus on one sport. This will make comparing and choosing the one with the best margin easier and faster. Punters should know that margins vary by sport, even on the same betting platform, and this can make the process challenging. Therefore, the general range for competitive odds in one major sport will likely not be the same for another sport. It won’t necessarily even be the same across betting regions around the world.

You may also want to narrow it down to specialising in a given betting market, e.g., Totals or Match Winner. This will give a true comparison of the odds and margins. Comparing completely different markets even within the same sport will not give a useful comparison.

Wagering on Betting Exchange

Another way to reduce the betting margin is by staking on betting exchanges. Getting a reasonable margin is easier since the odds here are determined by punters’ wagering activities. Betting exchanges only charge a commission when you win, as they don’t determine the odds margin. Luckily, the commission is typically lower than traditional betting platforms. The backing and laying of bet features is another useful tool to get a better betting margin. This allows you to identify the odds that are better and stake your funds on it.

Take Advantage of Promotions and Offers

With many offers like bonus matches and free bets, users can easily reduce online betting margins, and that plays a part in how bankroll management works. For instance, some bookmakers offer enhanced odds, reducing the margin, and potentially giving you an edge over the operator. Free bets, deposit matches, and similar offers can add free stacks to your profile, ensuring that you’re not risking only real money funds.

Identify Real Value in the Market

There are rare instances where the odds offered by bookmakers are higher than the actual odds of the event happening. This can be an error on the betting operator’s side, but if you have eyes for such occurrences, you can reduce the betting margin since the odds you stake on are higher than the actual ones. For instance, if the chance of a horse winning a race is calculated as 40% by a bookie and the actual value is 50%. Wagering in such a market will reduce betting overround.

Our top-of-the-line bookmakers

1.
Bet365
  • Bonus: Get $150 in Bonus Bets Win or Lose when you bet $5!
  • VIP Club, Loyalty Program
  • Cash Out, Partial Cash Out
Play Now
Subject to meeting qualifying criteria. Minimum wager $5. Minimum odds -500 or greater. $10 minimum deposit. Paid in Bonus Bets. Bonus Bets wager excluded from returns. New customers only. Available in app only. Max. prize, game restrictions, time limits and T&Cs apply.
2.
BetMGM
  • Bonus: Up To $1500 in Bonus Bets Paid Back if your First Bet Does Not Win
  • VIP Club, Loyalty Program
  • Cash Out, Live Streams
Play Now
T&Cs apply, 21+
Bank Transfer
Play+
PayPal
PayNearMe
+10
3.
FanDuel
  • Bonus: Bet $5 Get $250 in Bonus Bets IF YOU WIN
  • VIP Club
  • Cash Out, Live Streams
Play Now
T&Cs apply, 21+
Bank Transfer
Play+
PayPal
PayNearMe
+8
4.
Caesars
  • Bonus: Bet $1, Double Your Winnings Your Next 10 Bets
  • Loyalty Program
  • Cash Out, Live Streams
Bonus Code: ODDSPORTAL1000
Play Now
T&Cs apply, 21+
Bank Transfer
Play+
PayPal
PayNearMe
+9
5.
DraftKings
  • Bonus: Bet $5 and Get $150 in Bonus Bets Instantly!
  • VIP Club
  • Cash Out, Live Streams
Play Now
Bank Transfer
Play+
PayPal
VIP Preferred
+8
GAMBLING PROBLEM? CALL 1-800-GAMBLER, (800) 327-5050 or visit gamblinghelplinema.org (MA). Call 877-8-HOPENY/text HOPENY (467369) (NY).Please Gamble Responsibly. 888-789-7777/visit ccpg.org (CT), or visit www.mdgamblinghelp.org (MD). 21+ and present in most states. (18+ DC/KY/NH/WY). Void in ONT/OR/NH. Eligibility restrictions apply. On behalf of Boot Hill Casino & Resort (KS). 1 per new customer. $5+ first-time bet req. Max. $150 issued as non-withdrawable Bonus Bets that expire in 7 days (168 hours). Stake removed from payout. Terms: Promos | DraftKings Sportsbook. Ends 4/13/25 at 11:59 PM ET. Sponsored by DK

Online Betting Odds Formats

Betting odds are the probability of an event happening, and they determine how much a bettor can win while wagering. However, there are different formats of odds that bettors should know about. They make bet selections easier, and understanding these formats makes it easier to calculate a bookie’s overrounds. Check out the different types in the table below.

Decimal Odds (European Odds)This type of betting odds is common, and they are the easiest to understand. Odds here are in positive numbers, which makes it simple to calculate your potential winnings.

Multiply your stake with the odds, and the bet slip shows the amount you may win. The odds get higher when it’s unlikely for the event to happen and lower when the event is more likely to happen.

2.10, 3.0, and 1.56 are examples of decimal odds.
Fractional OddsThis format of betting odds in fractions is common in the UK. Calculate your potential winnings here using the formula below:
((numerator/denominator) +1) * stake.

Inserting your stake in your bet slip also reveals your winnings. But it’s not often used like the decimal odds, and its examples include 7/2, 7/1, and 10/1.
American Odds (Moneyline Odds)The moneyline, as it’s fondly called, is the third type of betting odds discussed in this section. It’s displayed in pairs, one number carrying a plus and the other a minus.

In a moneyline betting odds style, the odds with the negative signs are more likely to happen than the ones with the plus sign.

Fortunately, most betting sites will allow their users to choose their preferred formats. Thus, while being comfortable with all three types will certainly help you glean value insights on a bookie’s margins faster, you don’t necessarily need to become a pro at reading all three.

Sports With the Best Margins

Although odds and margins vary by betting platforms, some sports have very reasonable margins. This section of our online betting overround guide discusses some top sports with low margins.

  • Basketball: Basketball is one of the most followed sports in the world and it offers exciting betting markets. Bettors can also enjoy reasonable betting margins in basketball as this can lead to a profitable betting experience. Some betting options here include moneyline, point totals, handicap, etc.
  • Football: Football (soccer) has the highest number of followers amongst sports, and this extends to the global betting industry. With diverse leagues and tournaments available, punters can enjoy an impressive number of markets when they wager on football.
  • Tennis: Tennis governing bodies like the ATP, ITF, and WTA usually organise various tournaments every year, and this provides multiple betting markets for sports bettors. With many punters betting on tennis, many bookies offer low margins for tennis games. Some common markets here are match winners, total games, total sets, handicaps, etc.

Naturally, many online bookmakers tend to offer a low betting overround range for sports that are considered popular in the sports industry. However, what a bookie offers will also depend on your specific region, so if there’s a niche sport that is big in your country, your local bookies will likely compete to offer the best overrounds.

Other Terms Often Used Synonymously with Overround

Similar to what we saw in our accumulator guide, some betting terms go by various names. Frequently, other terms are used interchangeably with overround, so in this section, we’ll shed light on terms commonly used as synonyms. Even if you have a preference, knowing of these terms is crucial for any bettor aiming to understand general discussions around betting:

  • Vig
  • House Margin
  • House Edge
  • Juice
  • Payout

Be prepared to see these terms thrown out by experts and bettors, which will vary depending on the region you’re betting frome. Some might even argue the nuances between each term, but overall they point to the same concept.

Conclusion: Understanding Overround Meaning

Overround is an essential betting concept which is important for both bookmakers and punters. After reading our comprehensive guide, you should know what overround means, why it’s important, and how to calculate it.

Additionally, we have highlighted some sports with the best margins, odds formats that you may encounter when deducing the house profit margin, and some helpful tips to employ if seeking lower house margins. Finally, with some basic knowledge of terms that are frequently used synonymously with overround, you are much better prepared to be able to decipher what pros and casual bettors are referring to when using these terms.

The best online betting bonuses in 2025

1.
Bet365
Get $150 in Bonus Bets Win or Lose when you bet $5!
Play Now
Subject to meeting qualifying criteria. Minimum wager $5. Minimum odds -500 or greater. $10 minimum deposit. Paid in Bonus Bets. Bonus Bets wager excluded from returns. New customers only. Available in app only. Max. prize, game restrictions, time limits and T&Cs apply.
2.
BetMGM
Up To $1500 in Bonus Bets Paid Back if your First Bet Does Not Win
Play Now
T&Cs apply, 21+
Bank Transfer
Play+
PayPal
PayNearMe
+10
3.
FanDuel
Bet $5 Get $250 in Bonus Bets IF YOU WIN
Play Now
T&Cs apply, 21+
Bank Transfer
Play+
PayPal
PayNearMe
+8
4.
Caesars
Bet $1, Double Your Winnings Your Next 10 Bets
Bonus Code: ODDSPORTAL1000
Play Now
T&Cs apply, 21+
Bank Transfer
Play+
PayPal
PayNearMe
+9
5.
DraftKings
Bet $5 and Get $150 in Bonus Bets Instantly!
Play Now
Bank Transfer
Play+
PayPal
VIP Preferred
+8
GAMBLING PROBLEM? CALL 1-800-GAMBLER, (800) 327-5050 or visit gamblinghelplinema.org (MA). Call 877-8-HOPENY/text HOPENY (467369) (NY).Please Gamble Responsibly. 888-789-7777/visit ccpg.org (CT), or visit www.mdgamblinghelp.org (MD). 21+ and present in most states. (18+ DC/KY/NH/WY). Void in ONT/OR/NH. Eligibility restrictions apply. On behalf of Boot Hill Casino & Resort (KS). 1 per new customer. $5+ first-time bet req. Max. $150 issued as non-withdrawable Bonus Bets that expire in 7 days (168 hours). Stake removed from payout. Terms: Promos | DraftKings Sportsbook. Ends 4/13/25 at 11:59 PM ET. Sponsored by DK

Betting Overround FAQ

🤔 What’s overround in betting?

Betting overround is the total probability of all possible outcomes in a betting option. It usually exceeds 100% because bookies often have margins to make a profit.

👆 Are there differences between margins and overround?

No, the existence of margins in online betting odds results in overround. They perform the same goal, helping bookmakers to make a profit.

🔎 How does overround work?

Overround helps betting sites to make profits from stakes by including the margin in the odds. The percentage of the odds is guaranteed as a profit regardless of the outcome of the game.

⛔ Can I avoid margins?

It’s not very likely to avoid margins entirely, but by learning how to calculate margins, bettors can avoid betting sites with high overround.

🧮 Are overrounds easy to calculate?

Yes, overround calculation is quite easy, and it works for both 3-way and 2-way betting markets. You can check this article for a guide on how to calculate overround.

Close
Bet365
Bet365 Bonus
Subject to meeting qualifying criteria. Minimum wager $5. Minimum odds -500 or greater. $10 minimum deposit. Paid in Bonus Bets. Bonus Bets wager excluded from returns. New customers only. Available in app only. Max. prize, game restrictions, time limits and T&Cs apply.
Bonus Code
Go to Bet365
Visit Site
BetMGM
BetMGM Bonus
T&Cs apply, 21+
Bonus Code
Go to BetMGM
Get Bonus
FanDuel
FanDuel Bonus
T&Cs apply, 21+
Bonus Code
Go to FanDuel
Get Bonus