Li Chun marks the beginning of spring in the Chinese solar calendar. Jookaku uses a simple February 4 approximation for zodiac-year readings.
Li Chun, often translated as the Beginning of Spring, is one of the 24 solar terms in the traditional Chinese calendar. In many Feng Shui and BaZi-style systems, the yearly energetic shift is associated with Li Chun rather than the Western calendar's January 1.
For a lightweight web reading, Jookaku uses February 4 as a simple approximation. That means someone born in late January or the first few days of February may be treated as part of the previous zodiac year.
This keeps the calculator easy to use while signalling that Chinese metaphysics has its own calendar logic. For a precise traditional chart, consult a qualified practitioner.