Free Betting EV Calculator
Check if bookmaker odds offer value using expected value.
Bet Insights
Bookie vs You
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Expected Value (EV %)
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Projected Return (50 Bets)
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Minimum Value Odds
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Try our Kelly Criterion Calculator →
What is Expected Value (EV)?
Expected Value (EV) is a way of measuring whether a bet is profitable in the long run.
A positive EV means you are expected to make money over time, while a negative EV means you are expected to lose.
EV doesn’t predict single bets. It shows what happens over many bets.
How this calculator works
This tool compares your estimated win probability with the bookmaker’s implied probability from the odds.
It then calculates your expected value (EV), edge, and projected profit per bet.
Understanding EV
Imagine placing the same bet 100 times:
Stake: £10
Odds: 5.0 (4/1)
Win Chance: 30%
Wins
30 wins × £40 profit =
£1,200
Losses
70 losses × £10 =
£700
Net Profit
£1,200 − £700 =
+£500
Average EV
£500 ÷ 100 bets =
+£5 per bet
Even though many bets lose, over time this would be a profitable bet if your 30% estimate is accurate.
What is Implied Probability
Implied probability converts betting odds into a percentage that represents the bookmaker’s estimated chance of an outcome happening.
Example:
If the bookmaker’s decimal odds are 5.0, divide
1 ÷ 5.0 = 0.20.
Then convert to a percentage by multiplying by 100:
0.20 × 100 = 20% implied probability
What Is a Value Bet?
A value bet is when your estimated chance of winning is higher than the bookmaker’s implied probability.
Example:
Bookmaker odds = 5.0 (20% implied probability)
Your estimated chance = 30%
30% is higher than 20%, so this may be a value bet.
What is Expected Value (EV %)
Expected Value (EV %) shows the average percentage return or loss per bet based on your estimated probability compared to the bookmaker’s odds.
Example:
Wager: £1
Bookmaker odds: 5.0
Your estimated chance: 30%
Profit if you win: (5.0 − 1) × £1 = £4
Expected Value:
0.30 × £4 = £1.20
0.70 × (−£1) = −£0.70
EV = £1.20 − £0.70 = +£0.50
Meaning:
For every £1 bet, you expect an average profit of £0.50 in the long run.
This is equivalent to a 50% return on investment (ROI).
Projected Return (50 Bets)
This shows your estimated total profit or loss if you placed the same bet 50 times.
Example:
Wager: £1
Bookmaker odds: 5.0
Your estimated chance: 30%
Expected Value (per £1 bet): +£0.50
Projected Return (50 bets):
£0.50 × 50 = £25
Note: This is a long-term statistical projection and does not guarantee actual results.
Minimum Value Odds
The lowest odds at which a bet becomes profitable based on your estimated probability.
Tennis Example:
Bookmaker offers 5.0 on Emma Raducanu winning a match.
You estimate she has a 25% chance of winning.
Stake = £1
If she wins:
Profit = (5.0 − 1) × £1 = £4
Expected Value:
0.25 × £4 = £1.00
0.75 × (−£1) = −£0.75
EV = +£0.25 (profitable bet)
The calculator will display 4.00 as the minimum odds to look for.
Any odds above this value may represent a value bet (based on your estimate).
Meaning:
Any odds above 4.00 would be a value bet.
For example: 4.01, 4.10, 4.50 etc.
This assumes your 25% win probability estimate is accurate.
Value Betting Strategy Basics
- Bet on sports you understand. Knowledge helps you estimate probabilities more accurately.
- Compare bookmaker odds. Better prices can turn average bets into value bets.
- Think long term. Value betting works over many bets, not one result.
- Avoid emotional betting. Use logic, not loyalty to teams or players.
- Track your results. Reviewing bets helps improve your estimates over time.
Why EV matters in betting
- Helps identify value bets that others miss
- Removes emotion from betting decisions
- Focuses on long-term profit instead of single outcomes
- Lets you compare bets objectively
How to Use the EV Calculator
1. Enter your stake (£).
2. Enter the decimal odds from the bookmaker.
3. Enter your estimated win probability (%).
4. View EV, Edge, Projected Return, and Minimum Value Odds.
Output Explanation
EV: Your expected profit or loss per bet.
Edge (%): EV as a percentage of your stake.
Bookie vs You: Bookie's implied probability vs your estimate.
Projected Return (50 Bets): Estimated total profit/loss over 50 bets.
Minimum Value Odds: The lowest odds at which the bet becomes profitable.
This calculator is for educational purposes only. Betting involves risk.