Bookmaker overround explained: how the margin works and how to account for it

The bookmaker overround (also called the margin, vig or juice) is the percentage by which the implied probabilities in a bet market sum to more than 100%. On a standard 1X2 football market, the overround is typically 4–8%. This means bettors collectively lose 4–8% of every pound staked in the long run — regardless of their ability to pick winners. Understanding and accounting for the overround is the single most important structural concept in football betting, and it is the foundation of every AI expected value calculation.

Today's football predictions · Leagues · Guides