Where Do Sports Odds Come From?

Whether you've noticed them on Dimers.com or not, most of us have seen sports odds somewhere before and understand who is favored and who is the underdog. 

But, where do sports betting odds actually come from and how are they generated?

All of the answers are here for you, right now.

How are sports odds made?

The function of betting odds making isn’t to truly represent the probability of an outcome occurring. Vegas odds makers and the online sportsbooks actually put forth certain fractional odds to make a profit and in the hopes of attracting bettors to both sides (either team etc). 

Ultimately oddsmakers are in cahoots with sportsbooks. They are trying to reduce the risk of sportsbooks losing big. That’s why books hate when a big favorite wins, because they lose heavily. 

Betting odds certainly aren’t determined on the gut feel of a particular sports predicting genius. Sports statisticians and mathematicians are heavily involved in the odds you see on your sportsbook site and app. The X’s and O’s of sports odds comes from examination of the wider betting market, statistics and data.

MORE: What Sports Can I Bet On?

Why do sportsbooks have similar odds?

Sports betting is going gangbusters on a global scale. Surprisingly, sports betting is far more advanced in places like Australia, the United Kingdom and Asia, while it is just getting started here in the US.

Due to the globalization of sports betting, it isn’t uncommon for sportsbooks to simply copy the odds of other books. This method is cost effective and they end up with the same odds without all the data and betting analytics research. 

We don’t know which books copy others but we do know how you can find the best odds for every major sport in the United States.

MORE: How Do Risk-Free Bets Work?

How to take advantage of sportsbook odds

Sportsbooks look to make money off your bets, and set odds in such a way to favor their interests. So, how do we fight back and win money from sports betting?

The answer is simple — take advantage of the edge. What is the edge, you ask? 

This is where the probability of an event occurring is more likely than the sportsbook’s odds. In other words, our predictive analytics model suggests a team/player has better chances of a potential win than the sportsbooks' think! 

Taking these bets gives you a better chance of being a successful gambler long-term. Of course, the higher the edge, the better. While you’re not guaranteed a W, taking picks with an edge gives you a greater chance of being profitable well into the future. This is super important when trying to be a successful sports bettor.

For every major sports game including NFL, NBA, College Football and Basketball, MLB and more, Dimers shows you the edge and exclusive promotional codes to sign up with the sportsbooks.

MORE: What Are The Safest Online Sports Betting sites?

Why are odds not real probabilities?

Like any business, sportsbooks want to make a profit. They don’t sell clothes or shoes, but they do sell odds, to you, the bettor.

How do they profit? Let’s look below.


CFP National Championship - Moneyline 

Alabama Crimson Tide -250 (implied probability of 71.43%)

Clemson Tigers +200 (implied probability = 33.33%)

For all you super nerds out there, those percentages don’t add up. Well, they do, just not to 100% — don’t worry we had to use a calculator too.

The sum of the two percentages is 104.76%. How can a College Football game have two possible outcomes yet an implied probability of 104%? 

It can’t really. The extra 4% is the profit margin this sportsbook is taking home. With such a strategy — commonly implemented across America— a book will make a profit over time.

MORE: Where Does The Spead Come From?

Favorites lose = Sportsbook win

When there’s a big upset in any given sport, bookmakers rejoice. This is because most of the money is heavily poured on the favorite. 

At William Hill sportsbook — one of the best online books — 84% of the money was on the LA Rams to cover against the then 0-13 New York Jets in Week 14, 2020. Ultimately, they did not, with Gang Green winning outright. Big favorites losing is a sportsbook's golden goose, if you will.

Now that you know where they come from, find the best odds with Dimers. We have exclusive promo codes for each of the biggest and safest sportsbooks in America. If you’re wanting to succeed at sports betting, check out our Bet Hub for edgeds on all major sports.

Ready to join a Sportsbook and start betting online? We’ve listed the best available Welcome Offers for each legal betting state below.

The best offers in your state👇

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