See exactly how much margin a bookmaker has baked into a price. Enter the odds on each side of a market β we return the book's hold, its overround, and the raw implied probability behind every outcome.
| Outcome | Implied probability |
|---|---|
| 1 | 52.4% |
| 2 | 52.4% |
A fair, no-margin market always sums to exactly 100% implied probability β a true coin flip is 2.00 / 2.00. Bookmakers never price it that way; they price it a little short, at something like 1.91 / 1.91, so the two implied probabilities add up to more than 100%. That excess is the book's built-in edge, commonly called the vig, juice, margin, overround, or hold β the terms overlap in everyday use, but two of them mean precisely different things.
Overround is the raw excess: Ξ£(1/odds) β 1. On 1.91 / 1.91 that's (1/1.91 + 1/1.91) β 1 β 4.7%. Hold is a slightly different, more useful number: it's the share of a *balanced* two-sided book (equal money on every outcome) that the bookmaker keeps as profit, 1 β 1/Ξ£(1/odds). On the same 1.91 / 1.91 price, hold works out to about 4.5% β close to overround on tight markets, but the gap widens as prices get further from evens.
Why it matters: hold is the single cleanest number for comparing how expensive a bookmaker's pricing is. Sharp books like Pinnacle typically run a hold of around 2β3% on their main markets, because they compete on volume and accept sharp, well-informed action. Soft, recreational-facing books commonly run 5β7% or more, sometimes into double digits on props, parlays, and exotic markets. All else equal, a lower hold means a better, tighter, sharper price β and a smaller headwind for you to overcome before a bet is even worth considering.
Bookmaker hold is the share of a balanced two-sided book β equal money staked on every outcome β that the bookmaker keeps as guaranteed profit. It's calculated as 1 β 1/Ξ£(1/odds) across all outcomes in a market, and it's the built-in edge every bookmaker prices into every market.
Overround is the raw sum of implied probabilities minus 1 (Ξ£(1/odds) β 1). Hold is a slightly different figure β the fraction of a balanced book the bookmaker actually keeps as profit (1 β 1/Ξ£(1/odds)). Vig and juice are informal umbrella terms people use for either. On tight markets the two numbers are close; the gap widens as odds move further from evens.
It varies a lot by market and bookmaker. Sharp, high-volume books like Pinnacle typically run around 2β3% hold on their core markets. Soft, recreational-facing bookmakers commonly run 5β7% or higher, and props, parlays, and same-game combos regularly run into double digits.
Generally yes β a lower hold means the bookmaker is taking a smaller cut, so the prices are closer to the true fair odds. But hold is a market-level average, not a per-bet judgement: a market can have a low overall hold while a specific side within it is still overpriced relative to the true probability, so a low hold is a good sign, not a guarantee of value.