Enter one birth date to find your Japanese lunar mansion (Shukuyo birth mansion), old-calendar date, and calculation basis. No birth time, location, or sign-up is required.
Japanese old-calendar 27 mansions · Birth mansion and life themes
OpenFate converts a Gregorian birth date to a Japanese old-calendar month and day under a fixed JST convention, then advances through the canonical 27-mansion cycle to find the birth mansion.
A Shukuyo birth-mansion calculation needs one birth date, a defined Japanese old-calendar conversion, and a fixed 27-mansion sequence.
OpenFate exposes those layers so the result can be reproduced before any traditional meaning is added.
Use the recorded Gregorian date. Birth time, birthplace, gender, and account details do not affect this calculator.
The engine uses the JST civil date with defined new-moon, principal-solar-term, and leap-month handling to obtain the Japanese old-calendar month and day.
The old-calendar month supplies a fixed first-day mansion. Moving forward by the day number within the canonical 27-mansion sequence gives the birth mansion.
When results differ, compare the calendar convention, date boundary, time zone, and mansion count. Only after those facts match should traditional interpretation begin.
The calculation does not infer a personality, predict an event, or rank one mansion above another. It also does not use birth time, birthplace, gender, or a hidden 3 a.m. rollover.
Use the Shukuyo reading page to explore one calculated mansion, or the compatibility page to compare two mansions. Both routes reuse the deterministic result instead of asking AI to choose a new one.
Two birth dates are enough to compare both birth mansions, their relationship family and the role each person plays. Shukuyo compatibility
Follow the editorial standards, shared validation process and the exact method used for this system.
Sites can disagree because they use different old-calendar rules, time zones or month anchors. Follow the date, convention, checks and reading in order.
Sukuyo uses only the Gregorian birth date, read in Japan Standard Time with a midnight day boundary. Birth time and place are not inputs; a date beside a new moon near midnight is flagged.
The mansion comes from the old-calendar month’s fixed starting mansion plus the old-calendar day. OpenFate uses the modern Japanese anchor table, which differs from one historical T1299 chart, and states how it resolves the 2033 ambiguity.
OpenFate publishes dated calculation comparisons and their limitations. The implementation and full test fixtures remain private. This is not third-party certification or proof of predictive accuracy.
Read a full paid reading generated from a synthetic birth date, together with the automated checks it passed. It shows the reading style and its limits, not a prediction for you.
The single-person reading is designed around seven parts. It should synthesize the same calculated mansion rather than sell a more accurate chart or repeat the free result at greater length.
New reports are checked for all seven topics, supporting observations, counterexamples, repeated filler and unfinished text. Detected failures must be corrected before delivery as a completed report. These checks do not verify every interpretation or establish predictive accuracy; saved older reports remain unchanged.
Start with the free chart. Review the reading scope and example before deciding whether a deeper interpretation is useful to you.
Free charts and paid readings use the same chart calculations. Payment provides a complete interpretation; follow-up questions are charged according to your plan. Traditional readings support self-reflection and do not guarantee future events.
Answers about required birth data, the Japanese old calendar, 27 versus 28 mansions, and calculation differences.
No. The calculator only needs the recorded Gregorian birth date. It does not require a time, city, gender, or account.
The engine converts the date under a fixed JST Japanese old-calendar convention, finds the old-calendar month and day, then advances from that month’s fixed first-day mansion through the 27-mansion cycle.
Not in the 12-animal sense. The Japanese zodiac (eto) assigns an animal sign by birth year. This calculator finds your Shukuyo birth mansion, one of 27 lunar mansions taken from your birth date under the Japanese old calendar.
This calculator uses the Japanese Shukuyo cycle of 27 mansions. It does not mix in the Chinese 28-mansion system or another lunar-mansion table.
Sites may use different old-calendar conversions, time zones, leap-month rules, date boundaries, or 27-versus-28-mansion tables. Compare the stated method before comparing results.
No. A deterministic calendar engine calculates the old-calendar date and mansion. AI is not part of the result selection.
It uses the recorded Gregorian date under a JST civil-midnight convention. It does not silently move the date at 3 a.m. or infer a birthplace timezone.
The calculator shows the date conversion, birth mansion, and calculation basis. The separate Shukuyo reading page adds a deeper one-person interpretation without changing the calculated mansion.
Yes. From your result, open the free two-person lookup on the Shukuyo compatibility page. After you sign in and enter the second date, it shows both birth mansions, the relationship family, both directional roles, and any applicable distance band.
