Which date do people in Taiwan use to determine a Chinese zodiac sign?

I am trying to improve an English-language Chinese zodiac calculator and would appreciate some input from people in Taiwan.

This is the current version:

Disclosure: I maintain the linked website. I am not posting it as an authority on Taiwanese culture. I am sharing it because I would like to correct anything that is oversimplified or culturally inaccurate.

At the moment, the calculator primarily uses the birth year and warns people born in January or early February that they may belong to the previous zodiac year.

The more I read, the less straightforward the boundary seems.

For ordinary conversation in Taiwan, which rule would people normally use?

  1. The zodiac changes on January 1

  2. The zodiac changes at Lunar New Year

  3. The zodiac changes at 立春, usually around February 3 or 4

  4. It depends on whether someone is discussing 生肖, 八字, feng shui or annual fortune

For example, imagine someone was born on February 2 in a year when Lunar New Year began on February 10.

Would most Taiwanese people consider that person to have the animal sign of the previous lunar year?

Would a 八字 practitioner potentially use a different boundary based on 立春?

I also have a few terminology questions.

  • Is “Chinese zodiac” the most natural English translation of 生肖?

  • Should 羊 usually be translated as Goat, Sheep or Ram in a Taiwan-focused explanation?

  • When discussing the new year in a Taiwanese context, is “Lunar New Year” preferable to “Spring Festival”?

  • Are the five elements commonly considered part of a person’s everyday zodiac identity, or mostly relevant when someone requests a more detailed reading?

I am considering changing the calculator so that it requests the complete birth date rather than only the year. It could then clearly explain which convention it is using and show a warning when the date falls close to Lunar New Year or 立春.

Would that be more accurate, or would it still be misleading without the birth time and location?

I would especially appreciate corrections from Taiwanese members or anyone who has experience with local astrology and fortune-telling traditions.

Short answer, technically, the zodiac sign changes on the first day of a Schall von Bell year.

The long answer…

An East-Asian luni-solar year, without leap-month, is between 353 to 355 days. That makes it impossible to know when the first new moon (the definition of the lunar new year’s day) after the winter solstice (what keeps it luni-solar) is going to fall on just by tracking the number of days. The leap months are basically added to prevent the new year from taking place before the winter solstice, making it even more difficult to track.

During the Chinese dark ages (after the Mongols), people lost the ability to correlate the end of a solar year (Earth completing its rotation around the sun) with the coming of the next new moon (the moon completing its rotation around the Earth), which forced average people in China to celebrate the new year on the winter solstice, rather than on the first day of the first month.

That is why traditionally people say you are one year older after eating the round thingys (a.k.a. 圓仔, a.k.a. 湯圓) on the winter solstice.

As for 立春, that’s strictly a fortune telling thing. There are countless fortune teller groups and posts that are spreading the “The change of the zodiac signs has been on 立春 since ancient times” non-sense. It’s easily debunk-able.

For example, in Song Huiyao Jigao (‘Song Government Manuscript Compendium’ 宋會要輯稿), a passage goes:

「維治平四年, 歲次丁未, 正月庚戌朔,八日丁巳,英宗憲文肅武宣孝皇帝崩于福寧殿,旋殯于殿之西階。」

On the 4th year of Zhiping (era name for Emperor Yingzong of Song, 1067 CE), the year of Ding-Wei (the 44th year in the sexagenary cycle), First month of ganzhi Geng-Xu, 8th day of ganzhi Ding-Si (Janurary 25th 1067), Emperor Yingzong, Posthumous name Xianwen Suwu Filial-pious Emperor, died in Funing Palace, and his casket was soon placed near the western steps of the palace.

From this passage, it is clear that 丁未 (Deng-Wei) corresponds to the year of the goat, and this indicates the zodiac sign already changed from horse to goat on the First day of the First month (as the emperor died on the 8th day of the first month), and not on 立春, which was still still more than a week away.

It’s the only way I’ve heard people talking about it.

Just the character of 羊 itself could be any of those things. Traditionally I see people translate it as goat.

I’m biased on this subject. I believe we should name the calendar by the person who designed it, i.e. the Gregorian Calendar and the Gregorian new year. Therefore, it only makes sense to call the current East Asian luni-solar calendar the Schall von Bell Calendar, and the new year the Schall von Bell New Year.

Average people are fine with Lunar New Year. Spring Festival is usually used to refer to the entire holiday period.

Only relevant in fortune telling.

Taiwanese New Year

For the website, I wonder if you can provide corresponding earthly branches, and constellations on the ecliptic for each zodiac. For example, for the money: