Chinese calendar

The traditional Chinese calendar is a lunisolar calendar which reckons years, months and days according to astronomical phenomena. It is used for traditional activities in China and overseas Chinese communities. It determines the dates of traditional Chinese holidays, and guides Chinese people in selecting the most auspicious days for weddings, funerals, moving, or beginning a business.

In the Chinese calendar, the days begin and end at midnight. The months begin on the day with the dark (new) moon. The years begin with the dark moon near the midpoint between winter solstice and spring equinox. The solar terms are the important components of the Chinese calendar. In a month, there are one to three solar terms.

The currently used traditional Chinese calendar is the end result of centuries of evolution. Many astronomical and seasonal factors were added by ancient scientists, and people can reckon the date of natural phenomena such as the moon phase and tide upon the Chinese calendar. The Chinese calendar has over 100 variants, whose characteristics reflect the calendar's evolutionary path. As with Chinese characters, different variants are used in different parts of the Chinese cultural sphere.

In Korea, Vietnam, and the Ryukyu Islands, the Chinese calendar was adopted completely and evolved into Korean, Ryukyuan, and Vietnamese calendar, with the main difference being the use of different meridians which leads to same astronomical events falling on different dates in different countries and thus the same event may occasionally be assigned a different date in each of those calendars. The traditional Japanese calendar was also derived from the Chinese calendar, based on a Japanese meridian, however its official use in Japan was abolished in the early 20th century and its usage has mostly disappeared since then. Calendars in Mongolia and Tibet have absorbed elements from the Chinese calendar and elements from other systems, but they are not direct descendants of the Chinese calendar.

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