Free betting calculator
No-vig probability calculator
Remove a two-way sportsbook margin by normalizing both sides’ implied probabilities to 100%.
Enter positive odds with a plus sign or number, and negative odds with a minus sign.
Fair probabilities use proportional vig removal. They are estimates, not outcome predictions.
What the result means
Use the number as an estimate
Sportsbook prices usually imply probabilities totaling more than 100%. That excess is the hold. Dividing each side by the combined implied probability produces a transparent proportional no-vig estimate.
Two sides at -110 each imply 52.38%, or 104.76% combined. Normalizing both sides returns an estimated 50.00% fair probability for each.
How to use it
Check the inputs before the output
- 01
Enter both prices from the same two-way market.
- 02
Check the combined implied probability and sportsbook hold.
- 03
Compare each normalized fair probability and fair price with the best available offer.
Important limits
What the calculator cannot verify
- Proportional normalization is one estimation method, not objective truth.
- Both prices must use matching settlement rules and the same market.
- For three-way markets, use a calculator designed for all three outcomes.
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