East Asian age reckoning originated in China and continues in limited use there along with Tibet, Japan, Vietnam but is still common in Korea. People are born at the age of one, i.e. the first year of lifetime using an ordinal numeral, and on Chinese New Year or New Year's Day one year is added to their age. Since age is incremented at the beginning of the lunar or solar year, rather than on the anniversary of a birthday, people may be one or two years older in Asian reckoning than in the international age system.
Variations in date for change of age
Under the traditional reckoning in China, age changes on the first day of Chinese New Year. In Japan and South Korea, New Year's Day is used as the date of change of age for the traditional system.
China
In either the traditional or modern age system the wordsui, meaning "years of age", is used for age counting. In Chinese usage, there are three different types of age reckoning systems:
Traditional age, lit. "nominal age" based on the East Asian reckoning system
Both the "traditional age" and the "modern age" have lost much of its popularity within China, and the "real age" is nowadays the most commonly used age reckoning system in China. Of the three, only "real age" is legally used when reporting age in an official document such as the passport, ID card or a bank paper. The "real age" is also the only legally admissible to start drinking alcohol. The "real age" is the current Chinese legal system of age reckoning. When a child has survived one month of life a mun yuet celebration can be observed, in which duck or chicken eggs dyed red are distributed to guests to signify fertility.
Japan
The traditional Japanese system of age reckoning, or kazoedoshi, which incremented one's age on New Year's Day, was rendered obsolete by law in 1902 when Japan officially adopted the modern age system, known in Japanese as man nenrei. However, the traditional system was still commonly used, so in 1950 another law was established to encourage people to use the modern age system. Today the traditional system is used only by the elderly and in rural areas. Elsewhere its use is limited to traditional ceremonies, divinations, and obituaries. Japanese uses the word sai as a counter word for both the traditional and modern age system.
Korea
ns who use the traditional system refer to their age in units called sal, using Korean numerals in ordinal form. Thus, a person is one sal during the first calendar year of life, and ten sal during the tenth calendar year. The 100th-day anniversary of a baby is called baegil which literally means "a hundred days" in Korean, and is given a special celebration, marking the survival of what was once a period of high infant mortality. The first anniversary of birth named dol is likewise celebrated, and given even greater significance. South Koreans celebrate their birthdays, even though every South Korean gains one 'sal' on New Year's Day. Because the first year comes at birth and the second on the first day of the New Year, children born, for example, on December 29 will reach two years of age on the New Year's Day, when they are only days old. Hence, everyone born on the same calendar year effectively has the same age and can easily be calculated by the formula: Age = + 1 In modern South Korea the traditional system is used alongside the international age system which is referred to as "man-nai" in which "man" means "full" or "actual", and "nai" meaning "age". For example, man yeol sal means "full ten years", or "ten years old" in English. The Korean word dol means "years elapsed", identical to the English "years old", but is only used to refer to the first few birthdays. Cheotdol or simply dol refers to the first Western-equivalent birthday, dudol refers to the second, and so on. The traditional system has not been used in modern North Korea since the 1980s. South Korea is now considered as the only country that uses the East Asian age in the world and the term itself is well known as "Korean age" globally, rather than the East Asian age. The Korean Birthday Celebrations by the lunar calendar is called eumnyeok saeng-il and yangnyeok saeng-il is the birthday by Gregorian calendar. In the past, most people used the lunar calendar, eumnyeok saeng-il, to tell their birthday more than the Gregorian calendar yangnyeok saeng-il but nowadays Koreans, especially young generations, tend to use yangnyeok saeng-il for telling their birthdates. For official government uses, documents, and legal procedures, the international system is used. Regulations regarding age limits on beginning school, as well as the age of consent, are all based on this system. The age limit for tobacco, alcohol use are after January 1 of the year one's age turns to 19.
Vietnam
As being influenced by Chinese culture, the ancient Vietnamese also used this system and, despite not being the official age on papers and in daily usages at the present, the East Asian age is still limitedly used by adults, especially old people in rural areas. However, this age is not really familiar to the young generation. In Vietnam, it is called "tuổi mụ", "tuổi ta" or "tuổi âm".
In Eastern Mongolia, age is traditionally determined based on the number of full moons since conception for girls, and the number of new moons since birth for boys.
