Enter both sides of a bet from one sportsbook. See the book's cut (the vig or hold), the fair chance of each side, and the fair odds with the cut removed.
A sportsbook prices both sides so their implied chances add up to more than 100%. At -110 on both sides, each implies 52.4%, for 104.8% in total. The extra 4.8% is the book's cut, also called the vig, juice or hold.
Divide each side's implied chance by the total. At -115 / -105, the chances are 53.5% and 51.2%, adding to 104.7%. The fair chances are 53.5 / 104.7 = 51.1% and 48.9%, which are fair odds of -104 and +104.
Fair odds are the starting point for +EV betting: if another book offers better than the fair price, that bet has positive expected value. Our +EV list does this across every book for you.
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The sportsbook's cut, built into the prices so both sides add up to more than 100%. At -110 on both sides the vig is about 4.5% of what's bet.
The odds with the sportsbook's cut removed: the price that would be fair if the book took nothing. They show the market's real estimate of each side's chance.
A sharp, high-limit book or the average of several books gives the best estimate. Removing the vig from one soft book's prices still leaves its own mistakes in.