Sportsbook Margin Examples: What the Odds Are Charging
Worked examples showing how common two-way sportsbook prices translate into implied probability, market percentage and overround.
A two-way market priced at 1.91 on both sides implies about 104.71% in total probability, an overround of about 4.71%. That describes the posted price structure; it is not the same thing as guaranteed bookmaker profit.
Three simple two-way examples
| Odds | Market percentage | Overround | Normalized no-vig split |
|---|---|---|---|
| 1.91 / 1.91 | 104.71% | 4.71% | 50% / 50% |
| 1.95 / 1.95 | 102.56% | 2.56% | 50% / 50% |
| 1.80 / 2.10 | 103.17% | 3.17% | 53.85% / 46.15% |
Why “4.71% margin” needs context
Overround is calculated from the posted prices across a complete mutually exclusive market. It is useful for comparing price structures, but realized sportsbook hold depends on where customers bet, outcomes, limits, promotions and trading decisions.
How the no-vig column is produced
Each raw implied probability is divided by the total implied probability. That proportional normalization removes the displayed overround but does not prove the resulting percentages are the true probabilities.