Conventions & questions
Why can two calculators produce different figures for the same moment?
Check their conventions: Gregorian or lunar numbers, lunar ordinal or solar-term month, Lunar New Year or Start of Spring, a date change at 23:00, and the time zone used for the date. We map your local civil date to the Chinese lunar calendar and let you compare three alternatives. Classical texts do not specify modern time zones; these are disclosed conventions, not a claim of exclusive correctness.
What do the three switches change?
Solar-term months count Tiger month as one. The spring switch takes the year branch after Start of Spring. The late-hour switch uses the next lunar date from 23:00. A comparison holds the original moment fixed and shows the changed numbers.
Why do Heaven and Earth sometimes have no nuclear figure?
The classical exception says to take the nuclear figure of the changed figure for pure Heaven or Earth. With no moving line, neither has a changed figure, so we leave the nuclear figure absent. Other figures use lines two–three–four below and three–four–five above.
Does number casting include the hour?
The default divides each number by eight for the trigrams, then their sum by six for the moving line. Adding the local hour branch is a separate optional variant. Inputs are integers from 1 to 999999. A zero remainder means eight or six; a zero input is not accepted.
What does a share link reveal?
Free casting does not upload your question. A share link contains the numbers or time needed to reproduce the figure, which anyone holding the link can see. The question stays out of the link and is sent only when you request an AI reading or save it.
Does the matter I choose change the figure or its overall direction?
No. The matter is not part of the cast: the same casting inputs give the same original, nuclear and changed hexagrams, moving line, Body and Use and overall direction for every matter. It only selects which passage of the classic is quoted, from the section on the matter you chose: seeking wealth, an undertaking, recognition, marriage, going out, or human affairs in general. The passage reads the Body–Use relation the way the original does, not through the six-relation scheme of Liu Yao, and the same relation reads differently by matter: when the Use overcomes the Body, the wealth section says there is no wealth, while the recognition section says it cannot come.