Positive EV Betting Tool

What Is Positive EV Betting?

Positive EV, or positive expected value, betting is the concept of finding odds that are better than what the fair value for the specific wager should be. For example, imagine you’re at the grocery market and you can buy a ribeye steak for $2.00 cheaper than everywhere else, and $1.00 less than what you think the price should be, you’d be getting positive expected value on that ribeye steak.

Understanding fair value and devigging odds is important. Essentially, sportsbooks will insert vig or juice into their betting lines which can be calculated when looking at implied probabilities of both sides of a market. When you add the implied probabilities of both sides of a bet, they will oftentimes total over 100%. The amount above 100% is the market’s overround and reflects the sportsbook’s built-in vig.

Fair value odds are calculated by removing the vig so the combined implied probabilities equal 100%. A positive EV bet would be when a sportsbook offers a line that is even better than fair value odds. Our +EV tool calculates the fair value odds for you and identifies sportsbooks that beat that line, giving you an expected value edge.

Note that a positive expected value bet doesn’t mean that it’s a pick to win that particular outcome, rather it means that if the fair odds are accurate, consistently betting at prices better than fair value creates a positive expected return over a large enough sample.

How Does a Positive EV Betting Tool Find +EV Bets?

A good positive EV betting tool, like the one here at Prop Professor, has some unique formulas to establish the fair odds of a given market. I mentioned above how sportsbook vig can be removed to determine fair odds. That is one of several ways to devig a market. However, determining fair value can also involve considering multiple market prices and the quality of the sportsbooks providing those odds.

Our positive expected value betting tool uses sharper sportsbooks, such as Pinnacle, as reference points and applies devig methods to establish the fair odds for a given market. Then the tool compares available odds across 40+ sportsbooks to identify and highlight the best expected value opportunities.

Why Fair Odds and Devigging Matter

An easy way to understand a sportsbook's vig or juice is a basic 50/50 outcome-based event such as flipping a coin. You’re either getting heads or tails. The odds on a 50% implied probability event would be +100, however, if you’ve been around sportsbooks long enough you know that anytime there is a “coin-flip game,” sportsbooks may offer -110 odds on either side or a 52.4% implied win probability. That means that Tails would have to hit 52.4% of the time for you to break even. When you include the Heads side as well, the combined implied probability becomes 104.8%, creating an overround of 4.8 percentage points.

Understanding how to devig a line or recognize fair odds helps you identify better prices and improve your expected return rather than simply betting the first line you see.

Why Line Shopping Matters for +EV Betting

I alluded to this in the section above but if you don’t consider multiple sportsbooks for every market you’re betting on, you’re potentially leaving money on the table. Take for example our futures odds page, you may see Super Bowl odds for the Kansas City Chiefs that range anywhere from +800 to +1600 which is an $800 difference in potential profit on a winning $100 bet.

The same goes for any run-of-the-mill bet you look to place. A simple Los Angeles Dodgers moneyline bet could range anywhere from -180 to -220. At -180 a winning $100 wager returns about $55.56 in profit compared to $45.45 at -220. Over 10 winning $100 wagers, that difference adds up to roughly $100, or an extra unit. Think about how many bets you place in a week, month or year. Getting the best available price on all of those wagers makes it clear why line shopping matters.

Do Positive EV Bets Guarantee Profit?

Sports betting obviously carries risk and there are no truly guaranteed profit strategies. There will be winning and losing days using a positive EV betting strategy but consistently getting a better price than the estimated fair value is designed to produce a higher expected return.