Free tool
No-Vig Calculator
Equal-margin method · 2-way and 3-way markets
Enter the odds on every side of a market. The calculator strips out the bookmaker's margin and gives you the true probability, the fair price, and the size of the fee you were being charged.
| Outcome | Implied | True probability | Fair odds |
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Or skip the typing
Every price on this page had to be copied in by hand, one market at a time. We already did that for today’s football matches — every one the sharpest bookmaker prices, de-vigged the same way, updated through the day.
Free tier covers a fifth of each day’s matches, mixed across major and minor competitions. No card needed.
What the vig is
Any decimal price converts to a percentage by dividing 1 by it. A price of 2.00 is 50%; 4.00 is 25%. That is all an odd is — a chance, written differently.
Now take a two-way market priced 1.91 on both sides. Each converts to 52.4%. Together that is 104.8%, which is impossible: exactly one of the two things happens. The surplus 4.8% is the fee — the vig, the margin, the juice, the overround. You pay it whether you win or lose, and it appears on no receipt.
How the calculation works
Divide every raw percentage by their total. That is the entire method:
52.4 ÷ 104.8 = 50.0%
52.4 ÷ 104.8 = 50.0%
Total: 100%
What remains sums to exactly 100 and reads as a true probability. This is the equal-margin method, also called multiplicative de-vigging: every outcome gives up the same proportion of the fee.
Why the method has to be named
On a balanced market every de-vigging method agrees. On a lopsided one — a heavy favourite against a big underdog — equal-margin, odds-ratio, logarithmic and Shin all return different answers from identical prices. Any tool whose whole claim is “the real percentage” has to say which one it used. We use equal-margin, we say so, and we show the fee separately so you can redo the arithmetic yourself.
The full worked version, including where we take the prices from, is on the maths page.
What this does not do
A no-vig price is a measurement, not a prediction. It tells you what a market thinks with the fee removed. It does not tell you what to bet, and matching a market's accuracy is not enough to profit: a bettor who beat the closing price in every single game of a season still wins only slightly over 51%, below the 52.4% needed to break even at standard odds.