A calendar corrector is disclosed for arrangement in a movement of a watchmaking part provided with a calendar display and, for example, a thirty-one wheel which goes round in thirty-one days. In one implementation, the corrector comprises a manual control, enabling information relating to the fact that the current month comprises less than thirty-one days to be introduced, and programming means coupled to the thirty-one wheel, responding to the information introduced by the control, such that the display can be corrected automatically at the end of the current month.