What is edge in sports betting?
Edge measures the difference between a model's estimated probability and the probability implied by available odds.
Simple definition
If a model estimates a 70% chance and the available odds imply roughly 64%, the edge is about 6 percentage points.
How edge is calculated
Convert decimal odds into implied probability using 1/odds, then compare that number with the model estimate. Edge = estimated probability − implied probability.
Example: odds of 1.56 imply about 64.1%. If the model estimates 70%, the edge is approximately +5.9 percentage points.
Why positive edge does not guarantee a win
Edge is only as good as the probability estimate behind it. If the model overestimates an outcome, the apparent edge may not be real. Even a well-calibrated estimate can lose on an individual match.
Edge and price quality
The same estimated probability can produce a different edge at a different price. If market odds shorten, the amount of theoretical value also falls.
How SignalXI uses edge
Edge is one filter among several. SignalXI also considers probability, odds, EV, context and data quality before publishing.
Next: what is EV? →