The title compound, C(4)H(10)N(2)O, crystallizes with two independent molecules in the space group Cmc2(1). The first molecule lies in a crystallographic mirror plane with x = 0, whereas the second molecule lies on a general position with x is approximately equal to 1/3. Each molecule forms classical N-H...O=C hydrogen bonds, thereby leading to chains of molecules parallel or antiparallel, respectively, to the polar c axis.