The day boundary and true solar time
The chart records when the day pillar turns, and whether longitude pushes the hour pillar into the next cell. Zi Wei’s late-Zi rule does not stand in for this one.
Editorial review: 2026-09-22 · Reviewed by fateshow · Editorial method
The day can turn at 23:00 or at 00:00
BaZi here defaults to a 23:00 day change and can be switched to 00:00. Near that edge the two switches produce neighboring day pillars, and the whole ten-god table follows. Read which one the report used.
True solar time corrects the clock
True solar time shifts the clock by the birthplace longitude and is on by default. It can push the hour into the next cell. It does not add points. If the hour pillar changes when you turn it off, do not compare strength across the two charts.
An illustration at 23:10
Illustration: the clock says 23:10. With the day change at 23:00, the day pillar has already entered the next day. At 00:00 it is still the same day. If true solar time then pulls the clock back to 22:50, the hour pillar can also step back. All three sentences should be able to point at a switch on the chart. This is not a medical dispute about a birth record.
Common mistakes
- Treating Zi Wei’s late Zi at 23:00 as the BaZi day change.
- Hearing true solar time as a switch that makes the chart more magical.
- Picking a day pillar by feel when the birth sits on the edge.
Use it in fateshow
Frequently asked questions
Is the default 23:00 or 00:00?
The default is 23:00, and the chart can switch it. Use the day change printed on that report.
Are true solar time and the timezone correction the same?
Not quite. The historical timezone first restores the civil clock. True solar time then nudges it by longitude. Either one can move the hour pillar.
Does one minute matter?
It matters near a day boundary or an hour edge. Far from both, one minute usually stays in the same cell.
Sources and editorial basis
- 1. fateshow chart rule snapshot
Each generated report stores the engine settings that produced it. Compare those settings before treating two charts as the same calculation.
- 2. fateshow interpretation dictionary
Plain-language tendencies used in reports. They describe conditions and cautions, not fixed personality or inevitable outcomes.