How to Use the Expected Value Calculator
This expected value calculator (EV calculator) determines your profit margin over the sportsbook for a given wager. The calculator requires three inputs:
- Your stake: How much you're wagering (€100, €50, etc.)
- The odds: Decimal odds offered by the sportsbook (2.20, 1.91, etc.)
- Fair win probability: The true probability based on No Vig Price calculations
Finding Fair Win Probability
The fair win probability can be calculated using the no vig "fair" odds from a sharp sportsbook like Pinnacle. Finding the no vig fair odds from the sharpest sportsbook in the world is the industry standard for determining fair win probability.
Many bettors also use the Kelly Criterion to determine proper stake sizing based on their edge.
Expected Value Calculator Example
Let's say you bet €100 on Real Madrid at 2.10 odds (decimal) on Bet365. The sharpest sportsbook (Pinnacle) has Real Madrid at 2.00 odds and their opponent at 2.00 odds as well.
This means that the no vig "fair" odds are 2.00, and both teams have a fair win probability of 50%.
Calculation:
- Your odds: 2.10 (implies €110 profit on €100 stake)
- Fair win probability: 50% (from Pinnacle's 2.00 fair odds)
- Fair loss probability: 50%
Formula: EV = (fair win probability) × (profit if win) - (fair loss probability) × (stake)
EV = (50%) × €110 - (50%) × €100 = €55 - €50 = €5
This bet is profitable by €5, and placing positive expected value (+EV) bets like this one will make you profitable in the long run as a sports bettor.
When to Use the Expected Value Calculator
You should use the expected value calculator to ensure you are only placing bets where you have positive expected value.
Example: The Coin Flip
Imagine you're flipping a coin with a friend; that coin is 50/50 to land on heads or tails.
- At 2.00 odds (fair): EV of €100 coin flip = €0. Why flip the coin?
- At 2.10 odds (+EV): EV of €100 coin flip = €5. You should flip that coin as much as you can!
The same logic applies to sports betting. Only bet when the expected value is positive.
Expected Value Formula Explained
EV = (fair win probability) × (profit if win) - (fair loss probability) × (stake)
Breaking it down:
- Fair win probability: Based on devigged odds from Pinnacle
- Profit if win: (Your odds - 1) × stake (e.g., 2.10 odds on €100 = €110 profit)
- Fair loss probability: 100% - fair win probability
- Stake: Your wager amount
If the result is positive, you have a +EV bet. If negative, you have a -EV bet (avoid it).
Real Example with Sharp Sportsbook Reference
Let's say Liverpool's moneyline is 2.10 odds on FanDuel. The sharpest sportsbook (Pinnacle) has Liverpool at 2.00 and their opponent at 2.00 as well, meaning both teams have a 50% fair chance to win.
Your bet: €100 on Liverpool at 2.10 odds
EV calculation:
EV = (50%) × (€110 profit) - (50%) × (€100 stake)
EV = €55 - €50 = €5 profit
This is a +€5 EV bet, meaning it's profitable by €5 in expected value. Bet it!
Finding Positive EV Bets
This free calculator shows you HOW to calculate EV, but finding +EV opportunities manually across dozens of sportsbooks is time-consuming.
FairOdds Terminal automatically finds +EV bets across 60+ bookmakers in real-time by:
- Removing vig from Pinnacle's sharp odds
- Calculating No Vig Price for every market
- Comparing soft bookmaker odds to NVP
- Displaying only bets with positive expected value
Start your free trial to access automated +EV bet detection, arbitrage opportunities, and dropping odds monitoring.
Expected Value Calculator FAQ
What is expected value in sports betting?
Expected value (EV) is what you can expect to profit if you bet the same amount on the same odds repeatedly. Positive EV means you'll profit long-term. Negative EV means you'll lose long-term. EV helps you identify which bets are mathematically profitable.
How do you calculate expected value?
Formula: EV = (fair win probability × profit if win) - (fair loss probability × stake). Example: 50% chance to win €110, 50% chance to lose €100. EV = (0.50 × €110) - (0.50 × €100) = €55 - €50 = €5 profit.
When should I use an expected value calculator?
Use an EV calculator before every bet to ensure positive expected value. Compare the bookmaker's odds to fair odds (calculated from No Vig Price or sharp sportsbook like Pinnacle). Only bet when EV is positive to ensure long-term profitability.
What is a good expected value for a bet?
Any positive EV is profitable long-term. 1-2% EV is decent, 3-5% EV is excellent, 5%+ EV is exceptional. Even small edges (1-2%) compound significantly over thousands of bets to create substantial profits.
How do I find the fair win probability?
Use No Vig Price calculations from sharp sportsbooks like Pinnacle. Remove the vig from Pinnacle's odds to get fair probabilities. Alternatively, use statistical models or betting tools like FairOdds Terminal that calculate fair odds automatically.
Is expected value the same as guaranteed profit?
No. EV predicts long-term profit over many bets, not individual bet outcomes. You can have positive EV and still lose a bet due to variance. However, consistently betting positive EV ensures profitability over thousands of bets.