This calculator allows you to convert between different odds formats and see the implied probability. Simply enter odds in any format, and the other fields will update automatically. This helps you understand the true probability represented by odds in any format.
Implied probability is the conversion of betting odds into a percentage that represents the bookmaker's assessment of an outcome's likelihood. It reveals what the sportsbook believes is the true chance of an event occurring, plus their built-in profit margin (vig/juice).
For example, if a team has odds of -110, the implied probability is 52.38%. This means the bookmaker is pricing that outcome as if it has a 52.38% chance of happening. Understanding implied probability is crucial for identifying value bets where your assessment differs from the market.
For Negative Odds (favorites like -150):
Implied Probability = |Odds| / (|Odds| + 100)
Example: -150 odds → 150 / (150 + 100) = 150 / 250 = 60%
For Positive Odds (underdogs like +200):
Implied Probability = 100 / (Odds + 100)
Example: +200 odds → 100 / (200 + 100) = 100 / 300 = 33.33%
| American Odds | Decimal Odds | Fractional Odds | Implied Probability |
|---|---|---|---|
| -200 | 1.50 | 1/2 | 66.67% |
| -150 | 1.67 | 2/3 | 60.00% |
| -110 | 1.91 | 10/11 | 52.38% |
| +100 | 2.00 | 1/1 (Evens) | 50.00% |
| +150 | 2.50 | 3/2 | 40.00% |
| +200 | 3.00 | 2/1 | 33.33% |
| +300 | 4.00 | 3/1 | 25.00% |
The key to successful sports betting is finding situations where your assessed probability is higher than the implied probability from the odds. This is called finding "value."
Example:
Use our Edge Calculator to quantify exactly how much edge you have over the market, then use our Kelly Calculator to determine the optimal bet size.
When you convert both sides of a betting market to implied probability and add them together, they typically exceed 100% (often 105-110%). This difference is called the "overround" or "vig" and represents the bookmaker's profit margin.
Example: NFL Spread Market
The 4.76% represents the sportsbook's theoretical profit margin. Use our Hold Calculator to calculate the exact vig on any betting market.
This Implied Probability Calculator is great for converting individual odds - but what if you could see hundreds of player props with implied probabilities across all major sportsbooks side-by-side in real-time?
Professional bettors use odds screeners to:
JediBets Odds Screener includes:
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Note: Understanding different odds formats helps you spot value across different markets and regions. Many sharp bettors prefer decimal odds for easier mental math when calculating returns and comparing odds across multiple sportsbooks.