Widely used by people and for religious rituals before and after the Gregorian reform, the Mongolian traditional calendar which is a modified version of the Kalacakra calendar that originated in India is recognized as similar in function to the old calendars in other countries.
その代わり、インドに起源を持つ時輪暦を修正した暦が改暦以前から民間や宗教行事で広く使われていて、他国の旧暦に似た位置づけにある。