أحكام النساء
‘Ali (may Allah be pleased with him) reported: The Messenger of Allah (may Allah's peace and blessings be upon him) forbade that the woman shaves her head.
عن علي -رضي الله عنه- قال: نَهى رسول الله -صلى الله عليه وسلم- أن تَحْلِق المرأة رأسها.
شرح الحديث :
In this Hadīth, the Prophet (may Allah's peace and blessings be upon him) prohibited women from shaving their head, whether by a razor or shaving machine. This is because a woman's braids are equivalent to a man's beard, in terms of how they affect her appearance and add to her beauty. It is implicitly understood therefrom that it is permissible for a man to shave his head, without difference in scholarly opinions in this regard.