Who Sets the Odds for Sports Betting – 2024 Beginners Guide

Sports betting is one of the most popular ventures for gambling. A major reason behind that is it appeals to every gambler out there. Players who want to play safe and steady can enjoy sports betting passively. On the other hand, players who are risk-takers that go all-in for the underdogs to win big are also a big fan of sports betting. Depending on your luck and the betting odds, you can win big or lose hard. But who really decides that? Who gets to change the bets by judging how the match is going and which side the players are betting on? The answer to both of these questions is a bookmaker.

Regular bookmakers are people like you and me who set up and modify bets for their sports betting venture, while online bookmakers are online platforms that hire a team that compiles bets and presents lines for the betters to bet on. They are very experienced and clever. Analyzing and predicting which side the players will bet on and offering betting odds to players according to that is part of the bookmaker’s daily job. As a betting player, you must know how odds are calculated, how bookmakers earn their profit, and which bookmaker you should trust with your money. There are many shady unlicensed bookmakers out there that want to scam you out of your money. We heavily suggest avoiding bookmakers like these by researching online and referring to betting advising sites like which are more than happy to suggest you trustworthy booking sites.

If you haven’t placed sports bets before, or are not aware of things like odds calculation and bookmaker’s profit, then we recommend that you seek expert advice from sports information professionals like Doc’s Sports Service. Furthermore, reading this article will help you understand the entire process.

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How are betting odds calculated?


To show how betting odds are calculated, we’ll use a live example to demonstrate. Consider there is a football match between Real Madrid and Barcelona and the possibility of each outcome of the match is –

Real Madrid – 40%
Barcelona – 40%
Draw – 20%

Total – 100%

Easy right? All outcomes are probabilities that may happen and they all add up to 100%. However, these odds haven’t been touched by a bookmaker. A bookmaker will modify these odds by looking at the bets and make them more suitable for a bookie while also adding his own profit margin. Typical bookmaker margins are between 5-10%, depending on whether you won or lost your bet, and where you placed it. If you add the bookmaker’s margin to the outcome, your odds can change drastically, for example –

Real Madrid – 47%
Barcelona – 46%
Draw – 13%

Total – 106%

The extra 6% is the bookmaker’s margin. Thus, when you bet on sports betting and lose, you lose significantly more than you actually should. Your extra money goes straight into the bookmaker’s wallet. Bookmakers are proficient in setting up such betting odds that no matter what the outcome, they will always get rich. Of course, a bookmaker’s prediction can be wrong and when it is you can win big but you will rarely see that happen.

In an ideal environment, without the bookmaker’s margin, if you placed bets on all the outcomes you’ll get the profit of net-zero, nothing gained, nothing lost. However, we don’t live in an ideal world and if you were to do that in real life, you’ll suffer losses in the form of the bookmaker’s margin.

How bookmakers balance their odds.


A bookmaker always strives to create balanced betting odds. They don’t want players to all invest in one specific outcome, even if they lose. Now you might be wondering, wouldn’t it be better for the bookmaker if more people lost their bets? And the answer to that would be no, it doesn’t quite work like that. Let us explain.

Before every match, the bookmaker considers the situation and predicts where people are going to bet. He then sets his bets accordingly with his own margin added. When the betting starts, if people start betting on just one team/outcome, the bookmaker quickly adjusts the bets by increasing the margin on the bet everyone’s betting for and decreasing the margin on the less attractive bets which attracts players and encourages them to bet on it. This balances the bets again which increases the profit margin of the bookmaker.

A bookmaker only stands to profit if his betting book has balanced odds. The more the players with bad odds lose, the more the bookmakers have to payout winners who won with good odds, often resulting in a loss for the bookmaker. You can now see why not a single bookmaker wants this result – they lose a lot of money and that’s why balancing is so vital for a bookmaker.

How to find a bookmaker you can trust.


The matter of fact is that while all good bookmakers are going to make money one or the other way, some bookmakers rather use dishonest methods to cheat people off their money. There are several things you can do to save yourself from this scam –

Always play with licensed bookmakers. Licensed bookmakers are certified and authorized by the government to run a sports betting venture. Unlicensed bookmakers cannot be ever trusted, as they aren’t authorized by any sort of jurisdiction.

If it sounds too good to be true, it probably is. If the bets are being offered at unbelievable odds especially in favor of the winning team, then you might want to stay away from the bookmaker. No genuine bookmaker will publish unbalanced betting odds willingly.

Choose a bookmaker that suits you the best. There are several bookmakers available online that each offer unique bets for unique sports. If you are going to bet on one specific sport, as you should because then you need to research less, then we suggest you find one single sports betting site that fulfills all your needs.


Bookmakers are very clever people that have years of practice and experience in setting up bets. Understanding their method, their thinking and their aim can help you be a better sports betting player. We hope this article was insightful for you and helped you understand how the sports betting world works. If this article helped you then please do consider following our website for regular updates as it will help us out immensely.