What is EV Betting — Expected Value and Smart Betting

Example: Bet $10 - Win $11 - Expect to win $0.50 on every $10 flip = EV 0.5

A classic example of explaining what is EV betting is to use a coin flip. Let’s say you and your friend are flipping a coin. Every time it lands on tails, you win. For each flip, you bet $10. If it ends heads, you lose, and your friend wins $10. Between the two of you, you agreed that if it lands tails, you win $11. If you flip the coin repeatedly, you can expect to win an average of $0.50 on every $10 flip. The expected value (EV) of that bet is 0.5. Theoretically, if you flipped the coin 1,000 times, it would net you a profit of $500.

While EV betting is not a surefire way to start winning money, it dramatically improves your chances of finding smart bets with a positive value (EV+) that can yield positive returns over the long term. Calculating EV in betting also helps you avoid making bad wagers with a negative value (EV-). What you need to be prepared for is to:

1. Analyse matches to find value bets.
2. Learn the EV calculation and apply it whenever you evaluate the value of a bet.

You can think of EV in betting as learning the perfect Blackjack strategy combined with counting cards—you can improve your edge over the sportsbook if you successfully apply EV betting.

In this article, I’ll get into calculating EV in betting, along with more advanced examples compared to the coin flip example. After all, a coin flip is a bad example since you can expect the same outcome repeatedly, while an NBA, NFL, MLB, or NHL game is only played once. So, you’ll get a complete understanding of what is EV betting.

How Does EV Betting Work — Why It’s Important

• Positive Expected Value (EV+): A bet with a positive expected value (EV+) can be expected to return a profit in the long run. Just because a wager has a positive EV, it doesn’t guarantee it will win; it’s a theoretical measure that indicates that you will be profitable over the long term if you place this type of wager.
  
• Ideal Bets: Ideally, these are the only types of bets you would place. At the same time, when you calculate EV in betting and arrive at a negative expected value (EV-), you abstain from placing that wager.
  
• Straightforward Calculation: Using the EV betting calculation is fairly straightforward. The tricky part of applying expected value in betting is analyzing games to give you enough information and confidence to accurately appreciate a team’s chances of winning or scoring a certain amount of points or a player's achievement of what they need to cover a player prop bet.

Analyze and Assess Games and Create Your “Own” Odds

As you know, sportsbooks analyze and assess games to offer odds. They rely on their information and betting experts to calculate the probability of outcomes, which is then converted into odds that everyone can bet.

Your task is to do your own analysis and assessment of the game you want to bet on. This way, you can compare your prediction to that of the sportsbook. In this process, you create your own odds for the match, which you then compare with the sportsbook’s odds to determine if the expected value of the actual odds on offer is positive or negative.

Apply Expected Value When Evaluating Betting Predictions From Other Punters

An alternative to making your own analysis and assessment of the odds in a game is to apply the expected value to other punters’ predictions, as long as they disclose their analysis and what they think the true odds should be.

Trusting random betting predictions isn’t EV+ in itself. But there are reliable betting experts out there who regularly share predictions. Whether on Reddit, Discord or through paid subscriptions, winning bettors who share predictions exist. All you need to do is apply the EV betting calculation to get the expected value for the wager, which can help you decide whether to tail it or not.

How to Calculate Expected Value

To understand the EV calculation, using the sportsbook odds is easiest.

First, take the sportsbook odds and transform them into implied probabilities using the following formula:

• For Favorites (-): {negative odds} / ({negative odds} + 100) * 100 = implied probability.
• For Underdogs (+): 100 / ({positive odds} + 100) * 100 = implied probability.

We can use this formula in this example NHL game that we will then use to calculate the expected value:

Match	Home Team Odds	Away Team Odds	Implied Probability Home Team	Implied Probability Away Team
Boston Bruins @ Florida Panthers	-215	+176	68.25% (or 0.6825)	36.23% (or 0.3623)

You then use the following formula for calculating the expected value:

• ({decimal implied probability) * {$potential winnings}) - ({decimal implied probability) * {$stake}) = expected value

Using the example NHL game between Florida Panthers and Boston Bruins, with a $100 stake for Boston Bruins to Win at +176 odds, the expected value would be:

• (0.3623 * $176) - (0.6825 * $100) = -$4.485 (EV -4.485)

The EV is negative for this bet since you’ll lose $4.485 for every $100 staked. This is normal; every sportsbook odds you ever bet will have an expected negative value based on the bookies’ own estimations. Besides the true odds, the sportsbook adds vigorish (a fee) to ensure they can profit over the long run. In the example above, where you have a negative expected return of $4.485, the sportsbook has a positive expected return of $4.485 over the long run. But what’s missing here is your own estimation of the team’s chances of winning.

Calculating Your Own Probability and Applying It in EV Betting

You might arrive at a different estimate if you analyse the match between the Florida Panthers and the Boston Bruins. For example, you believe Boston has a 46% chance of winning instead of 36.23%. This would then mean that your odds for this game are:

Match	Home Team Odds	Away Team Odds	Implied Probability Home Team	Implied Probability Away Team
Boston Bruins @ Florida Panthers	-117	+118	54% (or 0.54)	46% (or 0.46)

Using the EV calculation on your own estimated odds, betting on the Boston Bruins is EV+ with an expected return of $0.28 for every $100 wagered over the long term:

• (0.46 * $118) - (0.54 * $100) = +$0.28 (EV +0.28)

While the expected value turned positive, it’s in neutral territory. Unless you’re certain about your analysis and you wager large amounts of money, it’s better to skip this one to find a better alternative with a higher EV.

How Can Expected Value Make You a Better Sports Bettor?

• Modern sportsbooks are highly accurate in pricing events, making it difficult to find odds that offer positive expected value (EV).
• More popular sports tend to have more accurate odds, reducing the chance of finding EV+ bets.
• EV+ bets are easier to find in niche markets, such as player props, NCAA basketball, the NBA G League, or smaller leagues, rather than major leagues like the NBA.
• Few professional bettors can beat NBA Moneylines, but more can succeed in less popular basketball leagues.
• Betting on major U.S. sports (Moneyline, spreads, Over/Under) generally offers less value due to near-perfect odds and difficulty in overcoming the vig over the long term.
• Finding a niche market, where sportsbooks are less knowledgeable, can lead to consistently finding EV+ bets.
• Specializing in a niche, such as cross-country skiing, can allow bettors to outperform sportsbooks and profit over time.

The “problem” with modern sports betting is that sportsbooks are so good at pricing events that the odds are rarely off. This means that it’s difficult to find matches with wrong odds and, subsequently, a positive EV.

As a general rule of thumb, the more popular a sport is, the more accurate the sportsbook odds will be. For example, you’ll have an easier time finding EV+ bets in player props rather than the main spread of an NBA game. Similarly, you’ll have an easier time finding EV+ bets in NCAA basketball, the NBA G League or the German Basketball Bundesliga compared to the NBA.

Very few professional bettors can beat NBA Moneylines, but a greater percentage of professional bettors can beat less popular basketball leagues.

This means that the expected value is less useful when betting major US sports Moneyline bets, main spreads, or Over/Under because sportsbook odds will be near perfect (over the long term). This means that your bets on these sports will have a negative expected value over the long term because you’ll have difficulty beating the vig.

Therefore, EV in betting becomes much more useful if you find a niche. For example, one of my colleagues I used to work with in a market-making company (we provided liquidity on sports betting exchanges like Betfair, SBO, and Matchbook) specialized in cross-country skiing and consistently beat all the sportsbooks for well over a decade because he had better knowledge about this sport compared to the sportsbooks. This allowed him to consistently find EV+ bets, making him a profitable bettor.

Positive Expected Value (EV+) and Negative Expected Value Bets (EV-)

Being successful at sports betting is a marathon race, not a sprint. It's similar to how a batter in the MLB doesn’t swing on everything that comes his way; you don’t have to bet on everything. An MLB batter would wait for the right pitch and take a swing; similarly, you should wait for the right betting opportunity to make a wager.

You should be patient and only take bets where you have determined a positive expected value (EV+). If you’re interested in a particular game and do your analysis and estimates but arrive at a negative expected value (EV-), you should skip wagering.

Professional punters prioritize quality over quantity; when they have a quality bet with solid EV+, they’ll bet heavily. They’ll skip EV- and marginal calls without any doubt.

Really, patience is vital to successful sports betting, and you should only take EV+ bets and avoid EV-bets.