How D8ly calculates a Bazi chart

Required inputs

• Local civil birth date and time
• Birthplace latitude and longitude
• The historical UTC offset at the birthplace and birth date

Calculation steps

1. 1. Normalize the supplied civil time

   The calculator treats the supplied date, time, coordinates, and UTC offset as authoritative. It does not silently guess a city, time zone, or daylight-saving transition.

2. 2. Correct toward True Solar Time

   Longitude correction and the Equation of Time adjust clock time toward local apparent solar time. This matters when the corrected time crosses a traditional two-hour boundary or calendar boundary.

3. 3. Calculate the Four Pillars

   The resulting moment is mapped to Year, Month, Day, and Hour pillars. Each pillar contains one Heavenly Stem and one Earthly Branch, producing the eight characters known as Bazi.

4. 4. Derive structured relationships

   D8ly derives the Day Master, Five Elements distribution, and deterministic stem and branch relationships from the calculated chart. Daily guidance compares that chart with an explicitly requested reading date.

Why D8ly requires the historical UTC offset

Time-zone rules change across countries and years. Requiring the offset makes the assumption visible and reproducible instead of hiding a potentially incorrect daylight-saving lookup inside the calculation.

Reproducibility and limits

• Missing birth time is not reconstructed or inferred.
• Coordinates and historical UTC offset are not guessed by the deterministic agent tools.
• Interpretation frameworks can vary between Bazi schools even when the underlying pillars match.
• Results describe a traditional reflection framework, not a scientific prediction or professional recommendation.