K-BaZi
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Saju chart calculator

Four pillars, five-element counts, and the calendar rules used to produce them.

Date of birth
Enter the date as it was recorded where the birth took place.
Lunar dates are not converted yet. Choosing Lunar returns a message instead of a chart, because no conversion is guessed in its place.
Time of birth
Nothing is substituted for an unknown time. The hour pillar is left uncalculated.
The list comes from the time-zone database already in your browser. Pick the zone for the place of birth; the offset in force on that date, including any daylight saving, is worked out from it. See what this changes.
Used only if a true solar time correction is switched on below. The site default leaves that correction off, so this field changes nothing unless you switch it on. No longitude is filled in for you.
Conventions used for this calculation These three change the result and are not decided by the data. The site default is shown first in each list. If you change one, the result notes that you set it rather than the site.
The default leaves this off because the longitude data it needs has not been collected, not because the tradition treats the correction as unnecessary. Switching it on requires a longitude in the field above.

Everything above is processed by this page in your browser. There is no account, no server request that carries these values, and no result URL that could contain them.

Calculation result

Nothing has been entered yet. When a date is entered, the four pillars appear here together with every calendar rule used to produce them.

3 rules unverified — 대표 기본값 2026-07-29 Three rules change what a chart says and are not decided by the data: which clock the solar term boundaries are read on, where the day boundary falls around 23:00, and whether a true solar time correction is applied. A default has been set for each one and every chart names the three it used. None of the three defaults has been independently verified. Each was chosen as the least weakly supported option, which is not the same as being correct. Each one can be changed in the form above. Candidates and their grounds: app/research/school-options.md.

Copies the characters above to the clipboard. Nothing is uploaded and no URL is created.

Reading the pillars

Four short notes on what each column is.

Year pillar

The pair attached to the year of birth. The animal that most readers already know sits in the branch of this pillar.

Month pillar

Decided by solar terms, not by the calendar month. This is the row where a boundary date changes the whole column.

Day pillar

The stem of this pillar is the reference point the tradition reads the rest of the chart against.

Hour pillar

Requires a time of birth and a time zone. Left uncalculated when either is missing.

Questions about this screen

Why does the time zone matter?
The offset in force at a place has changed over the years, and daylight saving has applied in some years and not others. Both can move the hour pillar, and one of them can move the day pillar.
What happens if I leave the time blank?
The hour pillar is left uncalculated and marked as such on screen. No midday default and no estimate is put in its place.
Can I get a link to this result?
No. No URL is created for a result. The characters can be copied as text with the button above, and that copy stays in your clipboard.
Is the result stored anywhere?
Nothing is written to a server, and nothing is written to this browser's storage. Closing the page ends it.
What are the three conventions, and can I change them?
Three choices change what a chart says and are not decided by the data: which clock the solar term boundaries are read on, where the day boundary falls around 23:00, and whether a true solar time correction is applied. Rather than pick one quietly, this site names the three it used next to every chart, and the form lets you change each one. None of the three defaults has been independently verified. Each was chosen as the least weakly supported option, which is not the same as being correct.
Why is the true solar time correction switched off by default?
Because the longitude data the correction needs has not been collected, not because the tradition treats the correction as unnecessary. Switching it on without a longitude returns a message rather than an estimated correction.