Convert odds to implied probabilities to better understand the true chance of winning and identify value bets.
What is Implied Probability?
Implied probability is the conversion of betting odds into a percentage, representing the bookmaker's assessment of the likelihood of an event occurring, plus their margin (also known as the "vig" or "juice").
Understanding implied probability is crucial for finding value bets. If your estimated probability of an outcome is higher than the implied probability from the odds, the bet may offer positive expected value.
This calculator allows you to convert odds in various formats to implied probability, as well as compare implied probabilities across multiple outcomes to calculate the bookmaker's margin.
Single Odds Calculator
Convert individual odds to implied probability.
Implied Probability:40.00%
The odds of 2.50 suggest that the bookmaker believes there is a 40% chance of this outcome occurring.
Bookmaker's Margin Calculator
Calculate the bookmaker's margin by entering all odds for a specific market.
Bookmaker's Margin
5.26%
The bookmaker's built-in profit margin
Total Implied Probability
105.26%
Sum of all implied probabilities
Fair Odds (Without Margin)
Outcome
Bookmaker Odds
Implied Probability
Fair Odds (Decimal)
What is a Bookmaker's Margin?
A bookmaker's margin (also known as "juice", "vig", or "overround") is the built-in profit margin that ensures the bookmaker makes money regardless of the outcome. It's calculated by summing the implied probabilities of all possible outcomes - in a fair market this would equal exactly 100%, but bookmakers set odds that imply a total probability greater than 100%.
A lower margin is better for bettors as it means more competitive odds and better potential returns. Professional bettors often compare margins across different bookmakers to find the best value.
Implied Probability Tips
Find value bets - Look for bets where your estimated probability exceeds the implied probability from the odds.
Compare across bookmakers - Different bookmakers offer different odds for the same event, which means different implied probabilities.
Calculate the margin - Lower margin markets typically offer better value, as bookmakers are taking less profit.
Factor in the margin - When comparing your own probability estimates to bookmaker odds, remember that their odds include a profit margin.
Use implied probability for bankroll management - Tools like the Kelly Criterion use probability to determine optimal stake sizes.