Shivratri occurs a day before every full moon. Maha Shivratri, in its true form, is a grand culmination of all the twelve monthly Shivratris that occur in a year. A grand celebration of this day is celebrated around the month of February-March, which also has many spiritual meanings. This year Mahashivratri is on 8 March .
https://www.vinaybajrangi.com/blog/festival/mahashivratri-2024