Four Pillars (BaZi) Chart — Basic Pillars
Enter a birth date and time to calculate the stem-and-branch pairs of the year, month, day and hour pillars. For births in Japan, on Japan Standard Time. No personality or fortune readings.
Available in Japanese and English
How it works
The year pillar changes at the moment of Lichun and the month pillar at each solar-term (jie) moment, both compared on Japan Standard Time. The day pillar changes at 0:00 and the hour pillar follows the JST clock time. With an unknown time, no hour pillar is shown, and the year and month pillars are marked as undetermined if a boundary falls on that date. Expected values were checked against independent sources: the National Astronomical Observatory of Japan (NAOJ) almanac solar-term times and its month stem-branch table, among others. This is a calendar calculation. It is not a reading of personality, fortune, health, money, marriage or work, and schools differ (day boundary, true-solar-time correction and so on).
6tail/lunar-javascript 1.7.7 (MIT) · 国立天文台 暦計算室 暦要項（二十四節気） · 国立天文台 暦Wiki「干支」The calendar library lunar-javascript (Copyright (c) 2018 6tail, MIT License) is included unmodified. Full license text