Value Bet Calculator
Calculate the expected value of any bet and strip out the bookmaker's margin to find the true fair odds. Two tools in one — identify value bets and understand what the book is really offering.
Quick presets:
Your Inputs
Your honest estimate — not the book's implied probability
Enter American odds (e.g. -110 or +150)
Amount you plan to wager
Verdict
Enter inputs to calculate
—
Implied Probability
--%
Book's probability embedded in these odds
Your Edge
--%
Your probability minus implied probability
EV per Bet
--
Average profit on this exact stake
EV per $100 Wagered
--
Normalized for comparison
Probability Comparison
Found a value bet? Use the Kelly Criterion Calculator to determine the optimal stake size based on your edge and bankroll.
Bookmaker Odds
Enter the odds the book is offering for each outcome. The tool removes the margin to reveal true fair odds.
American odds for Outcome A
American odds for Outcome B
e.g. soccer draw or 3-way moneyline
Common markets:
Total Implied Probability
--%
Sum before removing vig (should be >100%)
Book's Vig (Margin)
--%
Bookmaker's built-in profit margin
Fair Odds (Vig Removed)
| Outcome | Book Implied | Fair Prob. | Fair Decimal | Fair American |
|---|---|---|---|---|
| Enter odds above and click "Remove the Vig" | ||||
Understanding Value Betting
What Is Value Betting?
A value bet exists when your estimated probability of winning exceeds the probability implied by the bookmaker's odds. In other words: the book is offering better odds than the true likelihood warrants.
p = win prob, q = 1 − p, profit = stake × (decimal odds − 1)
Why Value Beats Parlays Long-Term
Parlays multiply your edge — but also multiply the book's vig. Each leg of a parlay compounds the bookmaker's margin against you. Betting single legs with positive EV is mathematically superior over large sample sizes. Parlays are lottery tickets; value betting is investing.
- ✓Positive EV compounds over time
- ✓Variance shrinks with volume
- ✗Parlays multiply vig per leg
Bankroll Management Note
Finding value is only half the battle. How much you stake per bet determines whether a positive edge translates into long-run profit or busts your bankroll during a variance stretch. The Kelly Criterion provides the mathematically optimal stake for any given edge.
Open Kelly Criterion CalculatorHow to Use This Tool
EV Mode — Find value bets: Enter your honest win probability estimate (not derived from the odds), the book's offered odds, and your intended stake. The tool tells you if this is a value bet and the long-run expectation.
Rule of thumb: If EV per $100 is positive, the bet has value at your estimated probability. If it's negative, the book has the edge.
No-Vig Mode — Find fair odds: Enter the odds for both sides of a market. The tool sums the implied probabilities (which exceed 100%), strips the excess (the vig), and shows you the true 50/50 fair odds.
Use case: Compare fair odds across books, or calculate the minimum probability you need to estimate for a bet to have positive expected value.
Common Vig Reference — What -110 / -110 Really Means
| Market | Odds A | Odds B | Total Implied | Vig % | Fair Odds Each |
|---|