Is the constellation based on the date of birth or the lunar calendar?

Constellations were introduced from the west, and they must be based on the western calendar, and they must be based on the month and day. If China people want to know their horoscope, they must convert their birth date into Gregorian calendar to know their exact horoscope.

If 1994.3.29 is the Gregorian calendar, you are Aries.

If 1994.3.29 is a lunar calendar, it is converted into a solar calendar, which means May 9th in the solar calendar, which means Taurus.

The most important thing here is whether the date you provide is Gregorian calendar or lunar calendar.