Win probability
What a win probability is, how SmartStake estimates it from sharp-book prices, and how to read the probability ring that appears on your bets.
What a win probability is
A win probability is our estimate of the true chance a bet has of winning, expressed as a percentage. A bet at 60% should win about six times in ten over a large sample. It is the single number that ties together everything else SmartStake computes: an edge is just your price being better than your win probability implies, and projected profit is that probability turned into dollars.
It is not the same as the price the book is offering. A book's odds imply a probability too, but that implied number is inflated by the book's margin — the vig. Strip the vig out and what remains is the fair probability. The win probability is our best read on that fair number, not the book's advertised one.
Where the number comes from
SmartStake estimates win probability from the sharp books — the books whose prices move the market and track true outcomes most closely. We take their current price on your bet, remove the margin to recover the no-vig fair odds, and convert that into a probability. For the detail on how the margin is removed, see devigging and fair value.
The short version: it is estimated from sharp-book prices and represents our best prediction for the bet, refreshed as those prices move. It is an estimate, not a certainty — a sharper line or a market that swings will move it.
Reading the ring
On your bets, win probability shows up as a ring around the bookmaker's logo, with the percentage spelled out when you open the bet. The ring is colour-coded so you can read it at a glance:
- Green — you are getting the better of the price; the bet wins more often than the odds you took suggest.
- Neutral — roughly a fair price, no meaningful edge either way.
- Red — you are on the wrong side of the price.
When we cannot price a bet — an obscure market, or a selection that is not in the sharp data — the ring shows an empty track and reads "Win probability unavailable" rather than guessing a number. That is expected for some markets and does not mean anything is wrong with the bet itself.
- Odds, prices, expected value, conversion rates, and profit figures shown are estimates based on the last data we retrieved. They can change at any time — confirm the current price at the book before you bet, as odds may move and entry errors can occur.
- Using a “sharp” book as a fair-value reference is a modeling choice, not a statement of accuracy. Review a book’s record yourself and anchor on the books you trust.