🧮 Free Tool

Value Bet Calculator

Enter your probability estimate and the bookmaker's odds. We'll tell you instantly if there's value — and exactly how much edge you have.

Your Probability Estimate
What do YOU think the true win probability is?
%
E.g. 55 = you think this outcome has a 55% chance of happening
Bookmaker Odds
The odds offered by the bookmaker
DEC
Your Probability
Implied Probability
Edge
Expected Value

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What is Value Betting?

A value bet exists when the bookmaker's implied probability is lower than your assessed true probability. The bookmaker is underestimating the likelihood of an outcome — and that gap is your edge.

If Bet365 prices Arsenal at 2.10 (implied: 47.6%), but your analysis says Arsenal win 55% of the time, you have a +7.4% edge. That's a value bet.

Edge = Your Probability − Implied Probability
Example: 55% − 47.6% = +7.4% edge

Over hundreds of bets, positive edge compounds into profit — regardless of individual results. Value betting is the only mathematically sustainable approach to sports betting.

Read our complete Value Betting Strategy Guide →

How to Use This Calculator

Step 1 — Estimate the true probability. This is the key skill. Use recent form, xG data, head-to-head records, and injury news to arrive at your own probability estimate for the outcome.

Step 2 — Enter the bookmaker odds. Find the best available odds (always compare across bookmakers). Enter in decimal, fractional, or American format.

Step 3 — Read the result. If Edge is positive and EV is positive, you have a value bet. Our threshold: we consider >5% edge worth betting.

EV = (Your Probability × Decimal Odds) − 1
Example: (0.55 × 2.10) − 1 = +0.155 = +15.5% EV

This calculator uses the same methodology documented in our editorial methodology page. Our value threshold is set at >6% edge divergence.

Best Bookmakers for Value Bettors
These operators offer consistently competitive odds and are known for not limiting winning accounts as aggressively as mainstream books.