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Every two-sided market carries the book's margin. Enter both prices and this strips it out: the estimated fair odds, the no-vig win probability, and how much hold you were being charged.
Use both sides of the same market at the same book: Over/Under, Team A/Team B, Yes/No. A sharp book's prices give the best proportional estimate — it's an estimate, not gospel.
Pricing a boost on this bet? Take the fair odds to the Profit Boost EV Calculator to get the edge in dollars.
Convert both prices to implied probability and they add up to more than 100%. That extra is the book's margin. Divide your side by the total and the margin is gone:
fair probability = your implied % ÷ (your implied % + other side implied %)
Worked example: −110 / −110 on a spread. Each side implies 52.4%, totalling 104.8%. Your side's fair probability is 52.4 ÷ 104.8 = 50%, which is +100. The book sold you a coin flip at −110 and kept the difference. This proportional method is the standard two-sided devig, and it's the same first step the desk runs on every play. The full method, including when it can mislead you, is in how to devig odds.
The odds a bet would have if the book took no margin: the market's honest estimate of the probability. It's the yardstick every bet should be measured against, because a bet only has edge if the price you get beats the fair price.
A boost is only worth something if it lifts your payout above the fair price. Boosting a bad price can still leave you below fair. Fair odds in, boost on top, and the boost EV calculator tells you if the result clears zero.
The sharpest market you can see, ideally where limits are high and lines move fast. Soft books copy sharp books, not the other way around. Averaging two or three books' devigged numbers is even better, which is what the desk does with a full consensus pull.
The desk devigs multi-book consensus on every boost, every day, and publishes the results, wins and losses both.