IsomorphicGraphQ
IsomorphicGraphQ[g1, g2] yields True if graphs g1 and g2 are isomorphic, and False otherwise.
Examples
Check isomorphism:
IsomorphicGraphQ[CycleGraph[5], CycleGraph[5]]
(* True *)Non-isomorphic graphs:
IsomorphicGraphQ[CycleGraph[4], PathGraph[Range[4]]]
(* False *)Please visit the official Wolfram Language Reference for more details.