Methodology
How Daymaster reads your chart
Daymaster reads two classical systems — Bazi (the Four Pillars) and Zi Wei Dou Shu (Purple Star Astrology) — in synthesis, and computes every chart from true solar time. Here is what those two choices mean, and why our results often differ from other tools.
True solar time (not the political timezone)
A chart’s hour pillar depends on where the sun actually was at the moment of birth — not on the time on your watch. Daymaster corrects clock time to true solar time using your birth longitude, and adds the Equation of Time (an offset of up to ~16 minutes across the year). For births near a timezone edge or close to an hour-branch boundary, this step often decides the hour pillar — and therefore the Life Palace and the whole chart. Using the political timezone is the single most common source of error in other tools.
Two systems, read as one
Bazi describes the inner cause: your energy, nature, and potential, centered on your Day Master. Zi Wei Dou Shu describes the outer effect: the concrete events that play out across twelve life palaces. Most products hand you two disconnected charts. Daymaster links them as a causal chain — "because the Bazi shows a certain structure, the Zi Wei shows a certain event in the corresponding palace" — which is exactly the synthesis a real practitioner performs.
Qi Men Dun Jia: reading the moment, not the birth
Bazi and Zi Wei read the moment you were born. Qi Men Dun Jia reads the moment you ask. The same person asking the same thing at two different times gets two different boards — not a contradiction but the method’s premise: one question, one moment, one board. Because it needs no birth data, anyone can cast one at any time.
We publish every convention the board is cast with: rotating plate, hour-based, Chai Bu for the Ju, Yang plate, 天禽 lodged in 坤2, true solar time. All five are printed on every board. We state them because Qi Men is more easily checked than any other system here — anyone can cast the same moment elsewhere and compare. Naming the school makes a difference legible as "we use Chai Bu and you are looking at a Zhi Run chart" rather than an accusation in either direction.
A versioned, proprietary engine
Chart construction, the fortune curve, and event scoring all run on our own engine, and every release is versioned. When the engine improves and would produce a different result for the same birth data, older readings surface a prompt to refresh — so what you see is always the most current, most accurate chart.
Common questions
Why does my Daymaster chart differ from other Bazi apps?
The most common reason is the hour pillar. Daymaster keys the hour to true solar time — clock time corrected to the sun’s actual position at your birth longitude — while many tools use the political timezone. Near a timezone’s edges this can shift the hour pillar by a full two-hour branch, which changes the chart.
What is the Equation of Time and why does Daymaster correct for it?
The sun does not cross the meridian at exactly 12:00 every day — it runs up to ~16 minutes early or late across the year (the Equation of Time). Within ~16 minutes of an hour-branch boundary that offset can flip the hour pillar, so Daymaster applies it on top of the longitude correction.
Which Qi Men Dun Jia school does Daymaster use?
Rotating-plate hour-based Qi Men (轉盤時家奇門) with the Chai Bu (拆補法) method for determining the Ju, the Yang-plate numerological tradition, 天禽 always lodged in 坤2, and true solar time. If another tool gives you a different board for the same moment, the usual cause is the Ju: Chai Bu assigns every day to the solar term actually in force, while the Zhi Run (置閏) school lets a five-day block carry across a term boundary. The two agree on most days and diverge within a few days of a boundary — a difference of school, not an error in either.
How are Bazi and Zi Wei Dou Shu combined?
Bazi is the inner-cause layer (why) — energy, nature, potential, anchored by the Day Master. Zi Wei Dou Shu is the outer-effect layer (what) — events across twelve palaces. Daymaster reads them as a causal chain ("because the Bazi shows X, the Zi Wei shows Y"), not as two disconnected charts.