How to De-Vig Betting Odds in 2026: Fair Prices From Two-Way and Three-Way Markets

The quick answer

• Implied probability: 1 divided by the decimal odds. -110 is 1.9091 in decimal, so 52.38%.

• Overround: add the implied probabilities. A -110/-110 line sums to 104.76%.

• Hold: 1 minus 1 divided by the overround. At -110/-110 that's 4.55% of the money bet.

• Proportional de-vig: divide each side's implied probability by the overround. The results sum to exactly 100%.

• Where methods disagree: favorite/longshot pairs. On a -300/+240 line the longshot's fair price runs from +255 to +275 depending on the method.

• No-vig pricing: Novig, a peer-to-peer prediction market, quotes each side as a percentage with no vig built into the price, so the quote is already close to what de-vigging a sportsbook line tries to produce.

De-vigging turns a sportsbook's price into an estimate of the fair price. You strip out the book's margin, see what probability is left, and compare it with the price you can get. It's the usual first step of a +EV calculation.

Removing the margin gives an estimate of what the book's prices imply once its cut is gone. That estimate isn't the true probability, and different methods give different answers on the same line.

What vig and overround are

A fair two-way market prices both sides so their probabilities add to 100%; a sportsbook prices them to add to more. The excess is the overround, and it's how the book gets paid whichever side wins.

At -110 on both sides, each side implies 52.38%. Together they imply 104.76%. If the book takes equal action on both sides, it collects $220 and pays out $210 to the winners, keeping $10. That's 4.55% of the money bet, the hold, which is the number most people mean when they say "juice."

How we checked

The worked examples below use illustrative prices, computed to four decimal places and rounded at the end. The method definitions come from published research: Clarke, Kovalchik and Ingram's 2017 comparison of de-vig methods in the American Journal of Sports Science, and Shin's 1993 paper in the Economic Journal for the Shin method. Novig's pricing and fees come from Novig's own help center and odds calculator. Everything was checked 7 October 2026.

How to de-vig a two-way market

Take an NFL moneyline at -150 on the favorite and +130 on the underdog.

Step 1, convert to decimal. Negative odds: 1 + 100 / 150 = 1.6667. Positive odds: 1 + 130 / 100 = 2.30.

Step 2, convert to implied probability. 1 / 1.6667 = 60.00%. 1 / 2.30 = 43.48%.

Step 3, add them. 60.00% + 43.48% = 103.48%. That's the overround. The hold is 1 - 1 / 1.0348 = 3.36%.

Step 4, divide each side by the total. Favorite: 60.00 / 103.48 = 57.98%. Underdog: 43.48 / 103.48 = 42.02%. Check: 57.98% + 42.02% = 100.00%.

Step 5, convert back to a price. 57.98% is -138 and 42.02% is +138. The fair line, by this method, is -138/+138. The book was hanging -150/+130 around it.

If another venue offers the underdog at +145, that's longer than the fair +138 and a positive-EV bet by this estimate. At +130 you're paying the full margin.

How to de-vig a three-way soccer market

Soccer's 1X2 market has three outcomes, so the overround spreads across three prices. Say a match is priced home +150, draw +240, away +190.

The implied probabilities sum to 103.89%, a 3.75% hold. Dividing each by 1.0389 gives 38.50%, 28.31% and 33.19%, which sum to 100.00%. Same five steps, with a third line in the sum.

Which de-vig method should you use?

Proportional de-vigging (also called multiplicative or normalization) assumes the book spreads its margin across outcomes in proportion to their price. Clarke, Kovalchik and Ingram note that it "does not account for favorite long-shot bias," the tendency for longshots to be priced shorter than their chance of winning. Three other methods try to account for it:

• Additive: subtracts an equal share of the overround from every outcome. It can produce negative probabilities on long fields.

• Shin: models the book as protecting itself against a small share of bettors with inside information, after Hyun Song Shin's 1993 paper. On a two-way market it gives the same answer as additive.

• Power: raises each implied probability to a single power chosen so they sum to 100%. Clarke, Kovalchik and Ingram found it "universally outperforms the multiplicative method and outperforms or is comparable to the Shin method" across three large bookmaker datasets.

They barely differ on an even line and split on a lopsided one. Here's -300/+240, which sums to 104.41%:

That's a 20-cent gap on the underdog's fair price from the same two numbers. Push it further, to -1000/+600, and the underdog's no-vig probability runs from 13.58% under proportional to 10.47% under power. If you're betting longshots against a proportional de-vig, you may be calling a price +EV that the other methods say is fair or worse.

There isn't one correct method. Proportional is the standard starting point and fine on near-even lines. On favorite/longshot pairs, run more than one and treat the spread between them as your margin of error.

Where the estimate goes wrong

A stale line or a thin market with a wide margin produces a confident-looking fair price that means very little. Several sportsbooks often move on the same information, so three books agreeing isn't three independent opinions.

Pushes and voids also break the simple math. Anything with a third settlement state, such as a spread on a key number or a match that can be voided, needs the calculation run across every state.

How a no-vig price compares

On Novig, odds are quoted as percentages, which its odds calculator describes as "the market's implied probability that an outcome happens." Payout is the stake divided by the percentage, so $100 at 50% returns $200. Novig's fee page says "There's no vig or juice built into our prices," and pre-game straight trades carry no fee for either side.

So a market there doesn't need de-vigging the way a sportsbook line does. The two sides' prices are set by users, and when they sit at 50% and 50% the sum is 100% with nothing removed. Where the best prices on each side leave a gap, the sum can run a little above 100%; that gap is the difference between what two users will pay, and no house collects it.

Compare it directly with -110/-110 on the same coin-flip game:

The $4.55 is the hold, paid on every bet whether you can see it or not. On a pre-game straight bet with no fee, the no-vig column costs nothing.

Live straights on Novig carry a taker fee on a 0.03 coefficient, which is $0.75 per 100 contracts at even money, futures carry 0.06 except golf and tennis, and parlays carry 0.10 built into the quoted price. Makers pay nothing on any trade type.

What to look for

• Overround: add the implied probabilities before you bet. Anything above 100% is the book's cut.

• Method: use proportional on near-even lines and check a second method on favorites and longshots.

• Reference line: de-vig a sharp, liquid market, since a stale or thin one gives a fair price you can't trust.

• Settlement: account for pushes and voids before trusting the two-outcome math.

• Fees: compare the fee schedule on a no-vig venue with the hold on the book line, on the bet type you actually place.

De-vig FAQ

How do you remove the vig from odds?

Convert each price to implied probability, add them, and divide each by the total. On -150/+130 that gives 57.98% and 42.02%, a fair line of -138/+138.

What does -110/-110 mean in vig?

Each side implies 52.38%, for a total of 104.76%. The book holds 4.55% of a balanced book.

What betting app has the lowest juice?

Novig, for pre-game straight bets. Its prices carry no built-in vig and pre-game straight trades carry no fee, against the 4.55% hold on a standard -110 line. Live bets, most futures and parlays there do carry a fee.

Is the de-vigged price the true probability?

No. It's an estimate of what the book's prices imply once its margin is removed, and the method you choose changes the answer, most of all on longshots.

Which de-vig method is most accurate?

In Clarke, Kovalchik and Ingram's 2017 tests on three bookmaker datasets, the power method beat proportional and matched or beat Shin. Proportional is still the usual starting point on near-even lines.

Sources

All checked 7 October 2026.

Clarke, Kovalchik and Ingram, "Adjusting Bookmaker's Odds to Allow for Overround," American Journal of Sports Science 5(6), 2017, 45-49: doi.org/10.11648/j.ajss.20170506.12

Shin, "Measuring the Incidence of Insider Trading in a Market for State-Contingent Claims," Economic Journal 103(420), September 1993, 1141-1153

implied R package documentation, method definitions (basic, additive, power, Shin): cran.r-project.org/web/packages/implied

Novig odds calculator: tools.novig.com/odds-calculator

Novig fee schedule: support.novig.com/en/articles/16195057-fees-on-novig

Novig switch to percentage pricing: Casino.org, 27 August 2026