Bookmaker Margin by Bet Type Cheat Sheet by BetBetter

Every price implies a chance: chance = 1 / decimal odds.

Add up the chances for every outcome in a market. A fair market adds up to exactly 100%. Anything above 100% is the bookma­ker's margin (also called the vig, juice or overro­und).

Example: both sides priced at 1.909 (American -110)
1 / 1.909 = 52.4% for each side
52.4% + 52.4% = 104.8%
Margin = about 4.8%

Two outcomes, decimal prices a and b:
Margin = 1/a + 1/b - 1

Three outcomes (home, draw, away): add all three chances, then subtract 1.

Fair (no-ma­rgin) chance of side A:
(1/a) / (1/a + 1/b)
For 1.909 v 1.909 this gives 50% each.

Convert any price format first: betbet­ter.wo­rld­/to­ols­/od­ds-­con­verter

Two-way match winner: about 4.8%
Over/under (totals): 5.6% in July, 6.4% in early September
Three-way (draw possible): about 7.5%
Player stats: about 7.6%

A bet on a player's statistics carried roughly 60% more margin than a simple match-­winner bet.

Player­-stat markets were also the biggest group: 23.8 million of the 69.6 million markets studied.

Lowest: baseball (MLB), 4.3%
Highest: intern­ational T20 cricket, 6.2%

The type of bet moved the margin more than the sport did: the gap between match-­winner and player­-stat bets (4.8% v 7.6%) is bigger than the gap between the cheapest and dearest sport.

69.6 million pre-game markets
53 providers, 14 sports
Observed 1 July to 8 September 2026

Each provider's prices were turned into chances; the margin is how far those chances add up above 100%, weighted by the number of markets. Compet­itions with fewer than 1,000 observ­ations were left out.

Full tables, free under CC BY 4.0: State of the Vig 2026

Margin / vig / overround: how far a market's implied chances add up above 100%.
Implied chance: 1 divided by the decimal price.
Fair chance: the implied chance with the margin taken out.
Two-way market: two possible results (win or lose, over or under).
Three-way market: a draw is also possible.
Player stats market: a bet on one player's numbers, such as points or strike­outs.