Strip the margin

No-Vig Calculator

Enter every outcome’s odds to get fair prices — then see the expected value of the bet you can actually get.

Bet slip · fair oddsLive

Expected value

−3.36%

EV per 100 staked−$3.36

Bookmaker margin3.48%

A fair-138 · 1.72 · 57.98%

B fair+138 · 2.38 · 42.02%

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Guides that go with this calculator.

Over/Under Betting: What Does Over Under Mean?

Over/under betting explained: what the total means, how -110 odds work, and a worked $100 example pa…

What Is Vig in Betting?

What is vig in betting? How vigorish works, with a −110/−110 example: 4.76% margin, 4.55% theoretica…

Kelly Criterion: How to Size Bets Using Your Edge

Learn the Kelly criterion with real numbers: a 55% win chance at evens gives a 10.00% full Kelly sta…

EV Betting: A Plain-English Guide to Positive EV

Learn EV betting with a worked example: a +150 bet at a 45% win chance has 12.50% EV and $12.50 expe…

FAQ

Frequently asked questions

What are no-vig (fair) odds?

The odds with the bookmaker’s margin removed. A −150 / +130 market has a 3.48% margin; without it the fair odds are -138 / +138.

How do you remove the vig?

Convert each price to an implied probability, add them up, then divide each probability by the total so they sum to 100% (the proportional method). Fair odds = 1 ÷ fair probability.

What is expected value (EV)?

How much a bet is worth on average, compared with the fair odds. Taking +130 when the fair price is +138 has an EV of −3.36%. Finding +145 elsewhere turns it into +2.94% — about $2.94 per $100 staked over the long run.

Is a positive-EV bet guaranteed to win?

No. EV is a long-run average; any single bet can lose. And “fair” odds here are only as good as the market they come from. Even −110/−110 with a +105 price elsewhere is just +2.50%.