Radius of a Graph Radius of a Graph can be calculated like this: rad(G):=min{ϵ(u)∣u∈V(G)}\operatorname{rad}(G):=\min \{\epsilon(u) \mid u \in V(G)\}rad(G):=min{ϵ(u)∣u∈V(G)} where ϵ\epsilonϵ is the Eccentricity.