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What is the vig? Finding no-vig fair odds on props

By JB, Slip Surgeon · Updated Oct 26, 2026

The vig (or juice) is the margin a sportsbook builds into its prices. On a single prop it's a few percent. Across a parlay it multiplies. Here's how to see it, remove it, and know what you're paying.

Spotting the vig

Convert both sides of a market to implied probability and add them. A fair coin flip would total 100%. A standard −110 / −110 prop totals 52.4% + 52.4% = 104.8%. The extra 4.8 points is the book's overround.

How to remove the vig (multiplicative method)

1. Convert each side to implied probability.
2. Add them to get the total (above 100%).
3. Divide each side by the total. The results add to 100% and are the market's no-vig, fair view.

There are other ways to split the margin (some methods assign more of it to the longer price), but the multiplicative method is simple, standard and close enough for props priced near even money.

Why the vig matters more in parlays

Each leg carries its own margin, and a parlay multiplies them. At −110 a leg returns about $95.45 per $100 on average if it's a true 50/50. Two such legs: $91.12. Four: $83.02. Six: $75.64. That's the math behind the how many legs question. You can see the margin on any slip by entering both sides of each leg in the parlay calculator.

Using no-vig odds to judge a leg

The no-vig number is the market's best guess with the margin removed. It isn't the truth, but it's a useful anchor: a leg only has a case if you have a reason to think its real chance is above the price's implied chance, not just above the no-vig chance. Our model starts from FanDuel's no-vig chance and moves away from it only when a second projection and recent form agree, and only by a capped amount. That's deliberate: it keeps us from overselling an edge. More on how the model works.

One-sided markets

Milestones, alternate lines and anytime touchdown props often have no posted opposite side, so you can't remove the vig directly. These markets usually carry more margin than main lines. If the same read is available on a main over/under, compare the two prices before you pick the milestone.

Frequently asked questions

What is vig in sports betting?

The vig (vigorish or juice) is the sportsbook's margin built into the odds. It's why both sides of a −110/−110 market add up to about 104.8% instead of 100%.

How do you calculate no-vig odds?

Convert both sides to implied probability, add them, and divide each side by the total. Convert the result back to odds for the fair price.

Check your own slip

Slip Surgery runs these checks on any NBA or NFL slip for free, then loads it into FanDuel or BetMGM.

Keep reading

Model picks, not locks. No checker can tell you a slip will win; it can only show you the price, the math and what changed. 21+ only. If betting stops being fun, call 1-800-GAMBLER or read our responsible gaming page.