Free Four Pillars BaZi calculator with true solar time.
BaZi Calculator (bazicalculator.pro) is a free, transparent tool for Chinese Four Pillars (BaZi) charts. Enter a birth date, time and place and it computes the year, month, day and hour pillars using true solar time by default (longitude plus equation of time), years from the exact Start of Spring instant, months from the twelve jie solar terms and a 23:00 day change. The chart shows the Day Master, Ten Gods for every stem and hidden stem, a transparent Five Elements count, and ten-year Luck Pillars with exact starting age. Every chart carries a rule-set ID so results are reproducible. Beyond BaZi, the site includes Zi Wei Dou Shu, Liu Yao coin casting, Mei Hua Yi Shu, Qi Men Dun Jia, a compatibility comparison without scores, a true solar time converter and a daily Chinese almanac. Calculation is free with no sign-up, and guides explain how to read a chart step by step. Results are for study and reflection, not professional advice.