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No-Vig Fair Odds Calculator

Remove the book's margin from a two-way or three-way market to get fair odds, the vig and the hold, by three methods.

American1.667 decimal

American2.300 decimal

Method

Divides each side's implied probability by the total. The usual default.

Price at another book (optional)

The same outcome at a different book, to see what it is worth against these fair odds.

American, decimal, fractional or a percent: -110, 2.50, 10/11, 52%

Fair odds for each outcome
OutcomeOfferedFair %Fair AmericanFair decimal
Side A-15057.98%-1381.725
Side B+13042.02%+1382.380
Vig (overround)3.48%how far the implied probabilities add up past 100%
Hold3.36%the share of the money bet a balanced book keeps

Fair odds: Side A 58.0% (-138), Side B 42.0% (+138). The book holds 3.36%.

How to use it

  1. Enter both prices of one market from the same book, in any format.
  2. For a soccer match result or any other three-way market, add the draw.
  3. Pick a method; proportional is the usual default.
  4. Optionally enter a price from another book to see its expected value against the fair odds.

The formula

Turn every price into its implied probability, measure how far they overshoot 100%, and scale them back.

implied = 1 / decimal, for each outcome
vig (overround) = sum of implied - 1
hold = 1 - 1 / sum of implied
fair probability (proportional) = implied / sum of implied
fair decimal = 1 / fair probability

-150 / +130: the prices imply 60.0% and 43.5%, 103.5% together. The vig is 3.5% and the hold 3.4%. Proportionally, the fair chances are 58.0% (-138) and 42.0% (+138). The power method gives 58.4% and 41.6%, the additive 58.3% and 41.7%.

  • Proportional. Divides each side's implied probability by the total. The usual default.
  • Power. Raises every implied probability to one power so they sum to 1, which takes more of the margin from the longer price.
  • Additive. Takes the same share of the margin off every side.

Edge cases

  • Use one book's prices for both sides. Prices from two books can add up to under 100%, which is not a margin to remove; the calculator flags it.
  • The methods agree on an even market: -110 / -110 is 50.0% each by all three. They differ most on long prices.
  • Three-way markets usually carry more margin than two-way ones, and the draw soaks up part of it; the table below shows the closing hold of each.
  • A market with only one price listed cannot be devigged: the other side is what tells you the margin.

From the odds Agatha tracks

What the books keep: closing hold

Median hold at the close over the last 30 days (since August 28, 2026), across 70,020 two-way moneyline markets.

The typical two-way moneyline closed with 4.88% of hold. The typical three-way moneyline closed with 6.70%. Book by book, it ran from 2.07% at 1xBet to 7.23% at PMU.

By league

Median closing hold by league, last 30 days
LeagueMarketMedian holdMarkets
NFLTwo-way moneyline4.50%2,239
MLBTwo-way moneyline4.51%25,737
NHLTwo-way moneyline4.58%466
CFLTwo-way moneyline4.61%695
WNBATwo-way moneyline4.74%1,807
NCAAFTwo-way moneyline4.83%10,544
UFCTwo-way moneyline4.91%2,261
ATPTwo-way moneyline5.11%8,907
WTATwo-way moneyline5.30%15,090
EsportsTwo-way moneyline6.94%2,274
La LigaThree-way moneyline5.26%132
Serie AThree-way moneyline6.06%110
MLSThree-way moneyline6.82%3,550
CFLSpread4.55%546
NFLSpread4.55%1,775
WNBASpread4.55%1,290
MLBSpread4.65%18,214
NCAAFSpread4.75%10,678
MLSSpread5.20%726
La LigaSpread5.54%107
NHLSpread6.17%347
UFCSpread6.37%131
EsportsSpread7.61%306
CFLTotal4.55%540
NCAAFTotal4.55%10,192
NFLTotal4.55%1,711
WNBATotal4.71%1,370
MLBTotal4.74%18,329
Serie ATotal5.35%100
La LigaTotal5.37%120
UFCTotal5.68%801
NHLTotal6.07%327
MLSTotal6.12%1,795
EsportsTotal7.62%520

By sportsbook, two-way moneylines

Median closing hold on two-way moneylines by sportsbook, last 30 days
SportsbookMedian holdMarkets
1xBet2.07%724
Pinnacle2.56%1,084
BetOnline3.28%1,055
BetUS3.41%855
FanDuel4.04%1,132
Caesars4.11%1,049
Unibet4.16%1,164
Bovada4.28%1,074
DraftKings4.35%1,106
Fanatics4.36%1,036
BetMGM4.43%1,116
Hard Rock4.49%1,108
Betfair4.55%591
Betway4.61%1,050
MyBookie4.63%964
Casumo4.74%696
BetRivers4.85%1,073
Sportsbet4.90%1,098
Ladbrokes5.03%1,135
Cloudbet5.03%444
Betfred5.04%808
Coral5.08%880
Superbet5.09%277
Betsson5.16%1,097
888sport5.17%812
Sky Bet5.26%341
William Hill5.26%862
BoyleSports5.31%778
bet3655.61%714
LiveScore Bet5.68%757
Tipico5.84%705
Winamax6.10%726
Rollbit6.26%630
Paddy Power6.38%831
Betano6.46%1,075
Stake6.68%653
BetVictor6.72%815
Roobet7.04%629
PMU7.23%386

As of . The sportsbooks Agatha tracks

No-vig calculator questions

What does no-vig mean?

No-vig odds are a market's prices with the book's margin taken out, so the chances add up to exactly 100%. -150 / +130 becomes -138 / +138.

What is the difference between vig and hold?

Both measure the margin. The vig (overround) is how far the implied probabilities add up past 100%: 3.5% in the example. The hold is the share of all the money bet that a balanced book keeps: 3.4%. Hold is always the smaller number.

Which devig method should I use?

Proportional is the common default and the easiest to check by hand. Power takes more of the margin from the longer price, a common adjustment for the long-standing finding that longshots are overpriced. On a close market the three barely differ.

Why would two prices add up to less than 100%?

Because they did not come from one market at one moment. One price is stale, or the two come from different books. Either way there is no margin to remove, and a gap that looks like value usually closes before it can be bet.

What can I do with fair odds?

Compare them with a price elsewhere: a price longer than fair is worth more than it costs. They are also how closing line value is measured without the vig; the CLV calculator does that for a bet you placed.