Hold (vig) calculator.
Enter both sides of a market and see the book's cut — plus what the fair, no-vig price would be. This is the math Big Mike runs on every line.
The app de-vigs every market on the board around the clock, so you never run this by hand. Chat with Big Mike ›How to calculate a sportsbook's hold
Add up the implied probabilities of both sides of a market and you get more than 100%. The excess is the hold — the book's margin for hosting the bet. Standard -110/-110 totals carry about 4.5%.
From hold to no-vig fair odds
Strip the hold out (normalize both probabilities to sum to 1) and you get the no-vig fair odds: the market's honest opinion. Comparing a book's posted price to the fair price across the whole market is exactly how The Edge board on this site finds +EV lines.
Common questions
What is a sportsbook's hold?
The margin built into the prices. At -110 both sides, implied probabilities are 52.4% + 52.4% = 104.8%; the extra 4.8 points (about 4.5% of the total) is the book's expected cut of all money bet.
How do you remove the vig to find fair odds?
Divide each side's implied probability by the total. At -110/-110: 52.4 ÷ 104.8 = 50% each side, so the no-vig fair price is +100 — which is why beating -110 long-term requires winning over 52.4%.
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