Vig calculator
Paste the odds for every side of one market and see exactly how much margin the book built in — or whether prices from two books sum under 100%.
The book keeps about 4.55% of balanced action on this market. No-vig prices: +100 (2.000) / +100 (2.000).
How the calculation works
A fair coin would be quoted +100 / +100 — 50% + 50% = 100%. A book quotes −110 / −110 instead: each side implies 52.38%, the pair sums to 104.76%, and the extra 4.76% is the overround. If bettors split their money evenly, the book pays out 100 for every 104.76 it takes in, keeping 4.76 / 104.76 ≈ 4.5% — the hold.
Three-way markets (soccer 1X2) work the same way with three sides. Alternate lines and props usually carry a much larger margin than main lines, which is why they rarely produce arbitrage.
Why it matters for arbitrage
Two books each holding 4.5% need to disagree by more than the combined margin before backing both sides at two books costs less than the payout. Low-vig books make that possible; our sportsbook rankings show which books actually run low margins on which sports, measured from live lines.
Frequently asked questions
How do you calculate vig?
Convert each side to an implied probability (for American odds: 100 / (odds + 100) for positives, |odds| / (|odds| + 100) for negatives; for decimal: 1 / odds), add them up, and subtract 100%. The excess is the overround. Hold is the overround divided by the sum, which is the share of balanced action the book keeps.
What is a normal vig?
Standard −110 / −110 pricing is a 4.76% overround (about 4.5% hold). Our live measurements of 20+ US books over 30 days put most between 3.5% and 7% overall, with reduced-juice books lower and pick'em-style apps higher. The current ranking is on the sportsbooks page.
What does a negative vig mean?
The implied probabilities sum to less than 100%, which never happens at a single book but does happen when you take the best price for each side from different books. That is a cross-book arbitrage; the dutching calculator splits the stake.
Related: Sportsbook vig, measured and ranked · What vig is · No-vig calculator · Dutching calculator
Educational tool. Verify every price on the venue before acting; nothing here is financial or betting advice.