Guide
No-vig odds
Last reviewed August 2026
What the vig is
Invert a decimal price and you get the probability the bookmaker is implying: 2.00 means 50%, 4.00 means 25%. Across a complete market those should sum to 100% — every possible result, adding to certainty. They never do.
Draw 3.40 → 29.41%
Away 3.90 → 25.64%
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102.67% ← overround 2.67%
Those 2.67 percentage points are the vig— vigorish, juice, margin, overround; the same thing under five names. It is the bookmaker's theoretical hold: bet every outcome in proportion and you lose 2.6% of your money with certainty.
The immediate consequence is that a price is not a probability. Every implied probability you read off a bookmaker is inflated, and it is inflated by an amount that varies by book, by sport and by market. Comparing raw implied probabilities across books compares margins as much as opinions.
The proportional method
The simplest correction assumes the margin was spread evenly and scales everything back down so the total is exactly 1.
home: 0.4762 / 1.0267 = 46.38% → fair odds 2.156
draw: 0.2941 / 1.0267 = 28.65% → fair odds 3.491
away: 0.2564 / 1.0267 = 24.97% → fair odds 4.004
The fair odds column is the break-even price for each outcome. A bookmaker offering more than 2.156 on the home win is paying above what the outcome is worth — that is a value bet, and its size is the difference. Try it on real numbers in the no-vig calculator.
When proportional is wrong
Proportional removal assumes the bookmaker applied its margin evenly across outcomes. Bookmakers do not. They load more margin onto longshots, because that is where recreational money concentrates and where customers are least price-sensitive — the well-documented favourite–longshot bias.
So proportional de-vigging systematically overstates a longshot's chanceand understates the favourite's. On a balanced market the error is negligible. On a lopsided one it can exceed a full percentage point — which is larger than most of the edges you would be acting on.
| Method | Model | Effect on longshots |
|---|---|---|
| Proportional | Margin spread evenly. | None — the baseline. |
| Shin | Book defends against a proportion of informed money. | Reduces them; well supported empirically. |
| Power | Fair probability is implied raised to a common exponent. | Strongest reduction. Suited to wide markets. |
| Odds ratio | Fair and implied odds ratios differ by a constant. | Between proportional and power. |
| Additive | Each outcome absorbs an equal absolute share. | Largest correction to longshots; often too aggressive. |
A conservative option: take the worst of all five
Running every method and keeping the lowest probability per outcome — the highest fair odds — means an edge only survives if the most pessimistic model still sees it. The resulting numbers deliberately sum to slightly under 1, so they are a filter rather than a probability distribution. GoldEdge supports this as a consensus mode.
Whose odds to de-vig
The arithmetic works on any price set. Whether the answer means anything depends entirely on whose prices they were, and this is the step most often skipped.
De-vigging assumes the quoted prices are an honest, informed estimate of the event with a fee added. That holds for a book with thin margins, high limits and no habit of banning winners — it cannot afford an inaccurate line, because sharp money would take it apart. Pinnacle is the standard choice for exactly this reason.
It does nothold for a recreational bookmaker, whose line is partly a commercial instrument for balancing its own customers' money. De-vig that and you get a confident-looking probability that estimates the book's marketing position rather than the match.
And de-vigging a book to compare against itself is circular — the edge is zero by construction. The point is always to de-vig the sharp book and compare against a different, softer one.
Frequently asked questions
What is the vig in betting?
The vig — short for vigorish, also called the overround, juice or margin — is the amount by which a bookmaker's implied probabilities exceed 100%. It is how the book makes money regardless of the result, and it is why a raw price is not a probability.
How do you calculate the overround?
Convert every outcome to an implied probability with 1/odds, add them up and subtract 1. A 1X2 market at 2.10 / 3.40 / 3.90 gives 47.62 + 29.41 + 25.64 = 102.67%, an overround of 2.67%.
What is a normal bookmaker margin?
Roughly 2–3% on major football markets at a sharp book like Pinnacle, and 5–10% at recreational bookmakers. Margins are much wider on minor leagues, exotic markets and outrights, where they can exceed 20%.
Which de-vig method should I use?
Proportional is a reasonable default for balanced two-way markets and is what most tools mean by no-vig. When prices are widely spread — a short favourite against a longshot — proportional overstates the longshot, and Shin or the power method handle it better. The differences are largest exactly where edges are hardest to judge.
Can I de-vig any bookmaker's odds?
You can perform the arithmetic on any price set, but it is only meaningful on a sharp book. The method assumes the prices reflect an honest, informed view of the event. A recreational book's line is partly set to balance its own customers' money, so de-vigging it produces a fair-looking number that estimates nothing.
Do you need every outcome to remove the vig?
Yes. The margin is defined across a complete, mutually exclusive set of outcomes — if a price is missing, there is nothing to normalise against. This is why a 1X2 market needs all three prices, and why a two-way de-vig of a three-way market is wrong rather than approximate.
For research, not betting advice. Positive expected value is an edge across many bets, never a prediction about one. Bet only what you can afford to lose. 18+.