Netherlands · Sports betting · Free tool
Sportsbook margin calculator: how much does the bookmaker keep?
Enter a sportsbook’s odds on every outcome of a market to see how much it keeps, the fair odds with its margin removed, and, with a second sportsbook’s odds, which pays more on each outcome.
Sportsbook margin calculator
Sportsbook A keeps
Payout 95.0%5.00%
Sportsbook A keeps about €5.00 of every €100 bet on this market, on average
- Overround (A)
- 5.26%
- Payout rate (A)
- 95.00%
- Book B keeps
- 3.90%
- Payout rate (B)
- 96.10%
- Fair odds, margin removed (A)
- 2.00 / 2.00
Sportsbook B keeps 1.10% less of every bet
Outcome by outcome
| Outcome | A | B | Better | Extra |
|---|---|---|---|---|
| 1 | 1.90 | 1.85 | Book A | +€5.00 |
| 2 | 1.90 | 2.00 | Book B | +€10.00 |
| 3 | — | — | — | — |
Margin assumes bets follow the fair probabilities (proportional method). Outcomes are in the order you entered them. “Extra” is how much more the better price returns on your stake if that outcome wins.
How the calculator works
A sportsbook never offers fair odds. Add up the implied probabilities of every outcome in a market and you get more than 100%: the excess is the overround, and it’s how the sportsbook makes money whoever wins. At 1.90 on both sides of a two-way market, each side implies 52.6%, together 105.3%, and the sportsbook keeps about 5% of everything staked on that market over time.
Enter the odds a sportsbook offers on each outcome, in decimal, fractional or American format, and the calculator shows how much it keeps, the share it pays back, and the fair odds with the margin removed. Add a second sportsbook’s odds on the same match to see which keeps less, and which pays more on each outcome. In the Netherlands the gambling tax is paid by the licensed operator, not taken from your bets, so the odds you see are what you get.
Typical margins
What a sportsbook keeps at common prices, computed with the same formula as the calculator.
| Market and prices | Overround | Sportsbook keeps | Pays back |
|---|---|---|---|
| Two-way market at 1.90 and 1.90 | 5.26% | 5.00% | 95.00% |
| Two-way market at 1.85 and 1.95 | 5.34% | 5.07% | 94.93% |
| Two-way market at 1.80 and 2.00 | 5.56% | 5.26% | 94.74% |
| Football 1X2 at 2.10, 3.40 and 3.50 | 5.60% | 5.31% | 94.69% |
| Football 1X2 at 2.25, 3.40 and 3.10 | 6.11% | 5.76% | 94.24% |
Frequently asked questions
What is the overround?
The amount by which a sportsbook’s implied probabilities add up to more than 100%. At 1.90 on both sides of a two-way market, each side implies 52.6%, together 105.3%, and the sportsbook keeps about 5% of everything staked on that market over time.
How is what the sportsbook keeps calculated?
Hold = 1 − 1 ÷ (sum of the implied probabilities), which is what the sportsbook keeps if bets follow the fair probabilities. The payout rate is the rest. The calculator removes the margin proportionally to get the fair odds.
Does a lower margin mean I will win?
No. It means you lose less on average. Even at a low margin, a bettor who picks at random loses part of everything staked over time.