No-vig odds are what a market's prices would be if the sportsbook took no margin. They are your quick estimate of fair value. You can calculate them in about 30 seconds with nothing but a phone calculator, or instantly with the no-vig calculator.
The 30-second method
- Convert each side to implied probability.
- Add them up.
- Divide each side by the total.
- Convert back to odds if you want.
Example: a moneyline
Sharp book: Team A −165, Team B +145.
- −165 → 165/265 = 62.26%. +145 → 100/245 = 40.82%.
- Total = 103.08%.
- Team A: 62.26 ÷ 1.0308 = 60.40%. Team B: 40.82 ÷ 1.0308 = 39.60%.
- Fair odds: Team A ≈ −153, Team B ≈ +153.
Now any book offering better than +153 on Team B, or better than −153 on Team A, is +EV against this fair line.
Example: a total
Over 47.5 −108 / Under 47.5 −112.
- −108 → 51.92%, −112 → 52.83%, total 104.75%
- Over fair: 49.57% (+102), Under fair: 50.43% (−102)
Example: soccer three-way
Home +140, Draw +240, Away +210.
- 41.67% + 29.41% + 32.26% = 103.34%
- Fair: Home 40.32% (+148), Draw 28.46% (+251), Away 31.22% (+220)
Three-way markets need all three prices. (Soccer three-way betting.)
Converting probability back to American odds
- If p ≥ 50%: odds = −(p ÷ (1 − p)) × 100
- If p < 50%: odds = +((1 − p) ÷ p) × 100
60.40% → −(0.604/0.396) × 100 = −153.
Which book's prices should you devig?
The no-vig line is only as good as the market you start from. Devigging a recreational book that shades its prices gives you a fair version of a biased line. Use a sharp book, an exchange, or a weighted blend. (What is a sharp sportsbook?.)
Proportional vs other methods
The method above is the multiplicative (proportional) method. It works well for near-even markets. For heavy favorites and longshots, other methods such as power or Shin give slightly different answers, and conservative bettors check all of them. (How to devig odds.)
What no-vig odds tell you at a glance
- Which side carries the margin. In the total example, the under is priced closer to fair than it looks.
- Whether your price is good. Compare it to the no-vig number, not the other side's price.
- How much a book is charging. A market with a 3% total is tighter than one at 6%.
The OddsHype odds screen shows a fair line beside every market so you never have to do this by hand.
Frequently asked questions
What are no-vig odds?
The odds a market would have without the sportsbook's margin, calculated by scaling each side's implied probability so they total 100%.
Is the no-vig line the true probability?
It is an estimate. From a sharp market it is a very good estimate; from a recreational book it can be biased.
How do I calculate no-vig odds for a spread?
Treat the two spread prices like a two-way moneyline: convert to implied probabilities, divide by their total, and convert back.