In the title compound, C(10)H(13)N(3)O, the hydrazinecarboxamide N-N-C(=O)-N unit is nearly planar [maximum deviation = 0.018 (2) Å] and is inclined at a dihedral angle of 8.45 (10)° with respect to the plane of the phenyl ring. The mol-ecular structure is stabilized by an intra-molecular C-H⋯O hydrogen bond which generates an S(6) ring motif. In the crystal, mol-ecules are linked into an inversion dimer by pairs of N-H⋯O and C-H⋯O hydrogen bonds.