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Implied Probability Calculator
Convert American odds to implied probability percentage. Understand the true win chance behind any betting line.
What is Implied Probability?
Implied probability is the win percentage that the sportsbook's odds suggest. It tells you how likely the book thinks an outcome is to happen.
Finding Value: If you believe a team has a 60% chance to win, but the implied probability is only 50%, you've found a value bet. The key to profitable betting is finding spots where your estimated probability exceeds the implied probability.
💀The Graveyard of Champions: Travers Stakes
See how the public's implied probability consistently overvalues Travers Stakes favorites—and how to profit from it.
Read Travers Stakes Guide →This calculator is for informational and educational purposes only. Results should be verified with your sportsbook before placing any wagers. All betting carries risk. Full Disclaimer
Frequently Asked Questions
How do I calculate implied probability from American odds?
For negative odds: |odds| / (|odds| + 100). So -150 implies 150/250 = 60%. For positive odds: 100 / (odds + 100). So +150 implies 100/250 = 40%. Implied probability is the break-even win rate for a bet at those odds.
Why do implied probabilities add up to more than 100%?
The excess over 100% is the sportsbook's margin, known as vig or overround. A standard -110/-110 line implies 52.4% + 52.4% = 104.8%, meaning the book keeps about 4.5% of the total handle regardless of outcome.
What is a good implied probability edge?
If your estimated true probability exceeds the implied probability by 2-5 percentage points after removing the vig, that is typically considered a solid edge. Sustained edges beyond 5% are rare in efficient markets like NFL sides.
What does -110 mean in implied probability?
-110 odds imply a 52.38% win probability (110/210). Since a fair coin flip is 50%, the extra 2.38% is the vig. You must win more than 52.38% of your -110 bets to profit long term.
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Responsible Gambling
Gambling should be entertaining, not a way to make money. Only bet what you can afford to lose, and never chase your losses.
- Betting more than you can afford to lose
- Chasing losses with bigger bets
- Lying to others about gambling habits