Your edge is the expected value of a bet as a share of your stake. It's positive when you win more often than the implied probability of the odds.
Edges in betting are small. A 2% to 5% edge on standard markets is excellent, and anyone claiming huge edges should be questioned.
The Kelly criterion uses your edge to size bets.
How it works
Edge is what every bettor is looking for, and it's smaller than most people think. Sportsbooks price markets carefully, and their margin means the average bettor starts with a negative edge.
An edge comes from two places: knowing the true chance of an outcome better than the market, and getting a good price. The second matters as much as the first. The same opinion can be a strong bet at one price and a poor one at another.
Where bettors tend to find an edge:
- Niche markets with lower limits, like lower leagues and prop bet markets.
- Early lines, before the market has fully adjusted.
- line shopping across several sportsbooks.
- Promotions that improve the price.
A useful reality check: consistent edges of 2% to 5% on standard markets are excellent. A capper claiming a 30% edge over a long period is very likely either on a lucky run or not showing the full picture.
Sportsbooks notice bettors with a real edge, often by tracking closing line value, and may limit their stakes.
Examples
- Example 1
You think a team wins 55% of the time and get -110. Your edge is 0.55 × 1.909 − 1 = +5.0%.
- Example 2
The same 55% view at -120 is only a +0.8% edge. The opinion hasn't changed, but the price has eaten most of the value.
- Example 3
A 52% chance at +100 gives a +4% edge, because even money only needs a 50% win rate to break even.
Common questions
What is a good edge in sports betting?
On main markets, a sustained edge of 2% to 5% is excellent. Larger edges are possible in niche markets, but they usually come with low betting limits.
How do I know if I have an edge?
Track your results over hundreds of bets, and compare your odds with the closing line. Consistently beating the closing line is one of the clearest signs of a real edge.