BaZi Four Pillars, 八字四柱, Chinese astrology birth chart, 生辰八字, heavenly stems earthly branches, 天干地支, year-month-day-hour pillars, Chinese natal chart, Ba Zi calculator, Day Master, 日主. Compute Four Pillars of Destiny (year/month/day/hour gan-zhi) from any Western birth datetime. Foundation of Chinese astrology analysis.