1-{3-[1-(Hydroxyimino)ethyl]-4-methyl-1H-pyrazol-5-yl}ethanone.

In the title compound, C(8)H(11)N(3)O(2), the oxime and the acetyl groups adopt a transoid conformation, while the pyrazole H atom is localized in the proximity of the acetyl group and is cis with respect to the acetyl O atom. In the crystal, dimers are formed as the result of hydrogen-bonding inter-actions involving the pyrazole NH group of one mol-ecule and the carbonyl O atom of another. The dimers are associated into sheets via O-H⋯N hydrogen bonds involving the oxime hydroxyl and the unprotonated pyrazole N atom, generating a macrocyclic motif with six mol-ecules.