No-Vig & EV Calculator
1 · Strip the vig
Enter both sides of a market to find the fair, no-vig price.
2 · Check expected value
Enter the price you can bet and your own estimate of the win probability.
A bet is +EV when your win probability beats the break-even rate the price implies. The no-vig fair % from step 1 is a sharp baseline for that estimate — if you can beat the fair price at another book, that gap is your edge.
Why the vig hides the real number
Add up the implied probabilities on both sides of any market and you'll get more than 100%. That overround is the vig — the book's built-in margin. Removing it scales both probabilities back to a true 100%, revealing what the market actually thinks each side's chances are. That is the fair, or no-vig, price.
Once you have a fair probability, you can measure a bet the only way that matters: expected value. If your estimate of a team's chances is higher than the break-even rate the price implies, the bet is +EV — it makes money over the long run even if any single bet loses.
This is the same logic our model runs at scale. Instead of eyeballing a no-vig number off one market, it builds a true line from the underlying data and bets only when the edge clears a tested threshold.
Frequently asked questions
What does removing the vig mean?
Sportsbooks price both sides of a market so the implied probabilities add up to more than 100%. That extra is the vig. Removing it — normalizing both probabilities back to 100% — reveals the book's true estimate of each side, called the no-vig or fair price.
How do you calculate expected value on a bet?
EV = (win probability × profit if you win) − (loss probability × stake). At +130 (you win $130 per $100) with a 48% win chance, EV per $100 = 0.48 × 130 − 0.52 × 100 = +$10.40 — a positive-EV bet.
Why use the no-vig price as my win probability?
The no-vig price from a sharp market is one of the best publicly available estimates of true probability. If you can bet a side at better odds than its fair price somewhere else, the difference is your edge.