Perpetual Chinese Calendar

LunarCal  User's Guide

10 Celestial Stems (Tian Gan) and 12 Earthly Branches Di Zhi)

Principal Terms - Zhong Qi

Sectional Terms - Jie Qi

Since the Chinese Lunar Calendar is lunisolar, the Principal and Sectional terms are important and forms an integral part of it. They are used to enumerate the calendar. A lunisolar calendar accurately predicts the seasons and hence can be used to aid farming activities. In contrast, pure lunar calendars cannot be used by farmers as the calendar gives no indication of the solar seasons and moves out of alignment with respect to the seasons as the years goes by.

In the Chinese Lunar calendar, the 1^st lunar month is associated with Spring while 11^th lunar month is Winter.

Note: Seasons are used in the Beijing, China (northern hemisphere) context.