Overround is the total implied probability of every outcome in a market, minus 100%. A two-way market at -110 / -110 adds up to 104.76%, an overround of 4.76%.
The bigger the overround, the more the sportsbook keeps. Main markets in major sports often run at 4% to 5%. futures and big fields like golf can run at 20% or more.
It's closely related to the vig, which expresses the margin as a share of the money staked.
How it works
Overround is the easiest way to see how much margin a sportsbook has built into a whole market. Add up the implied probability of every outcome, then subtract 100%.
It works for any market size. A two-way game has two prices to add. A soccer match result has three. A golf tournament can have more than 150. The more outcomes there are, the more room a sportsbook has to add margin without it being obvious, which is why futures markets often carry a large overround.
| Market | Typical overround |
|---|---|
| Main spreads and totals | Around 4% to 5% |
| Reduced-juice lines | Around 2% to 3% |
| Player props | Often higher |
| Futures and big fields | Often 20% or more |
Overround and vig describe the same margin in different ways. Overround is measured against 100%, while vig is the share of your stake the sportsbook expects to keep. For -110 / -110, the overround is 4.76% and the vig is 4.55%. In the UK, a market's total is often called the book percentage.
Examples
- Example 1
A soccer match priced +150 / +240 / +190 adds up to 40% + 29.41% + 34.48% = 103.89%, an overround of 3.89%.
- Example 2
A market at -105 / -105 adds up to 102.44%, so the overround is 2.44%.
- Example 3
If a 20-team championship market adds up to 130%, the overround is 30%.
Common questions
How do you calculate the overround?
Convert every outcome's odds to implied probability (1 ÷ decimal odds), add them up and subtract 100%.
What is a good overround?
Lower is better for bettors. Around 2% to 3% is sharp pricing for a two-way market. Main US lines at -110 run at about 4.76%.
Is overround the same as vig?
They measure the same margin. Overround is the total implied probability above 100%, while vig is the share of stakes the sportsbook expects to keep.