In graph theory, the out-degree [1] of a vertex in a directed graph is the number of directed edges with as tail. Its counterpart is the in-degree, the number of directed edges with as head.

Definition


Definition 1 (Out-degree)

Let be a directed graph and a vertex. The out-degree of is the number of directed edges in with as tail.

Notation


The out-degree of is denoted .

References

  1. [1]

    “Indegree and outdegree”, Wikipedia, Available: https://en.wikipedia.org/wiki/Directed_graph#Indegree_and_outdegree, Accessed: 2026-07-31