Vig & Overround Calculator
Enter the prices for a market and this measures the margin baked into them — the overround, the margin, the theoretical hold, and which outcome is carrying it. Everything runs in your browser.
- Overround
- 104.76%
- Margin
- 4.76%
- Hold
- 4.55%
| Outcome | Price | Implied | Margin carried | Share |
|---|---|---|---|---|
| Outcome 1 | -110 | 52.38% | 2.38% | 50.0% |
| Outcome 2 | -110 | 52.38% | 2.38% | 50.0% |
“Margin carried” splits the total margin across the outcomes: removing it proportionally takes each implied probability down by its own share, and the parts add back to exactly the 4.76% above. To see the prices with the margin actually taken out, use the no-vig calculator.
Overround, booksum, margin and vig are four names people use for the same idea; hold is the one that genuinely differs. Margin is the booksum minus 100%. Hold is that margin as a share of the booksum. For a −110/−110 market the margin is about 4.76% and the hold about 4.55% — close enough to be conflated constantly, and further apart the wider the market.
Informational and educational only. 18+. This tool performs arithmetic on figures you enter; it does not recommend any outcome and makes no prediction.
How margin and hold move apart
The same five market shapes, measured. Note how margin and hold sit almost on top of each other on a tight two-way market and separate as the market widens — that gap is why the two words are not interchangeable. Every figure is computed by the code the calculator runs.
| Market | Overround | Margin | Hold |
|---|---|---|---|
| Two-way, tight | 102.46% | 2.46% | 2.40% |
| Two-way, standard | 104.76% | 4.76% | 4.55% |
| Two-way, wide | 111.11% | 11.11% | 10.00% |
| Three-way | 104.81% | 4.81% | 4.59% |
| Four-way score | 104.61% | 4.61% | 4.41% |
Margin is not constant: thinner and less certain markets carry more of it, because the padding covers uncertainty as well as edge. That is exactly why two markets can’t be compared until the margin has been taken out of each — which is what the no-vig calculator does. For the concepts, see vig, de-vigging, and the vig explained.
Vig, overround and hold questions
- What is the vig?
- The vig — also called the margin, the juice, or the overround — is the amount by which a market’s implied probabilities add up to more than 100%. Two outcomes priced at −110 each imply 52.38% apiece, or 104.76% together. That extra 4.76% is the margin.
- Are vig and overround the same thing?
- In everyday use, yes. "Overround" usually names the total (104.76%) and "margin" or "vig" the excess over 100% (4.76%), but plenty of people use them interchangeably for the same idea. This calculator shows both numbers explicitly so there is nothing to guess.
- What is the difference between margin and hold?
- Margin is the booksum minus 100%. Hold is that margin as a share of the booksum — the theoretical proportion of staked money retained. They are close on a tight market (4.76% and 4.55% at −110/−110) and drift further apart the wider the market gets, which is why quoting one as the other is a real error rather than a rounding one.
- What does "margin carried" mean?
- It splits the total margin across the outcomes. Removing the margin proportionally takes each implied probability down by its own share, and those parts add back to exactly the total. It answers whether a market is padded evenly or whether one side is doing the work.
- How do I get the fair odds once I know the margin?
- Use the no-vig calculator — that is the tool that removes the margin and returns the margin-free probabilities and prices. This page deliberately stops at measuring it.
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