Why ChatGPT gets your Saju wrong
General AI chatbots like ChatGPT usually get your Saju (四柱, Four Pillars) wrong because they recite the calendar math from memory instead of computing it. In our own side-by-side tests they often miss two of the four pillars — most often month and hour. Saju is deterministic: the chart must be calculated, not guessed.
The four ways it slips
1. Solar terms (節氣), not the calendar date
The Saju year and month don't change on January 1 or the lunar new year — they change on solar terms, the sun's actual position. The year flips at 입춘 (Lichun, around Feb 4), and each month flips at its own term. A general chatbot uses the wrong boundary, so anyone born in early February — or near any month edge — gets the wrong year or month pillar.
2. True solar time (眞太陽時), not clock time
The hour pillar depends on where the sun was above your birthplace, not the number on the clock. Clock time is set to a standard meridian for a whole timezone; your real local solar time can be 30+ minutes off. Chatbots use raw clock time, so the hour pillar slips whenever you're born near a two-hour branch boundary.
3. Daylight saving time (DST), including the historical ones
If daylight saving was in effect when you were born, the clock was an hour ahead. Korea ran DST during the 1987–88 Olympics years; the US, UK and others have decades of DST history. Chatbots forget this and land the hour pillar an hour off.
4. The day-pillar formula, where centuries and leap years trip it up
The day pillar runs through the 60-stem-branch cycle continuously. Chatbots memorize a formula but slip on century and leap-year corrections, so the day pillar — the most important pillar, your 'day master' — can be wrong outright.
How Gwiraedang gets it right
The chart is deterministic, so we compute it instead of guessing: solar terms from VSOP87 solar longitude with ΔT correction, true solar time from your birth longitude, and historical daylight saving. The result is checked against the Korea Astronomy and Space Science Institute (KASI) to within ±1–2 minutes and locked by golden tests. Only the math is by code — five AI counselors then read that exact chart with you, in your own language.
Is ChatGPT accurate for Saju or BaZi?
Usually not for the chart itself. It often miscalculates the four pillars (especially month and hour) because it guesses the solar-term, true-solar-time and daylight-saving math instead of computing it. It can talk about Saju well, but the underlying chart it builds is frequently wrong.
Why do Saju and BaZi apps give different results for the same birth time?
Because they handle the calendar math differently — or skip it. Solar terms, true solar time, and daylight saving each leave room to disagree: apps split on the hour pillar depending on whether true solar time is applied, and on the year and month pillars depending on how the solar-term boundaries are drawn. Gwiraedang settles all three by direct astronomical calculation, and shows you on the result screen exactly which corrections were applied.
Is ChatGPT consistent — does it give the same Saju answer every time?
No. Ask a general chatbot about the same chart, in the same words, and it answers differently each time, because it generates a fresh reply on every request. A Saju chart is deterministic: the same birth input always produces the same chart, and we lock that with golden tests. If yesterday's reading and today's don't match, that isn't Saju — it's improvisation.
Does the AI remember our past conversations?
Yes. Gwiraedang keeps what you talked about last time and asks about it when you return — because a Saju reading isn't one-and-done; it accumulates as you come back. You can clear that memory anytime in settings.
How is Gwiraedang different?
Gwiraedang calculates your chart with a deterministic in-house 만세력 (myeongnyeok) engine — solar terms from VSOP87 solar longitude with ΔT correction, true solar time from your birth longitude, and historical daylight saving — then verifies it against the Korea Astronomy and Space Science Institute (KASI) to within ±1–2 minutes, locked by golden tests. Only the calculation is by code; the conversation is by AI.
What should I do to get an accurate reading?
Get your chart from a real 만세력 engine rather than a general chatbot. Enter your birth date, time and city — Gwiraedang handles overseas birthplaces (timezone and daylight saving) automatically — and then talk it through, in your own language.
See your chart, computed correctly
Birth date, time and city — overseas birthplaces handled automatically. Free.
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