Fate Hall v6.7 · 2026-10-31

BaZi (Four Pillars of Destiny), the I Ching and Korean folk fortunes side by side with Western astrology, tarot and numerology. Enter your birth date once and see East and West together.

Your details · time settings

Your details

Name (optional) Name in Hanja (optional)Only for Korean name analysis (Seongmyeonghak), which counts Chinese-character strokes. Full birth name (optional, for numerology) MBTI (optional) Blood type (optional)Blood-type personality is pop-culture lore in Korea and Japan, used here for fun.

Sex at birth

BaZi uses it to set the direction of your Luck Pillars.

Calendar

Date of birth

Time of birth

Place of birth Type your city to find it, or pick the country, then the city. Used for your local solar time; it stays in your browser.

Find your cityOr pick the country, then the city below.

Country City

I don’t know my birth time

Time basisClocks follow your time zone’s standard meridian, so the Sun at your birthplace can run minutes ahead of or behind the clock. Longitude correction fixes that offset; true solar time also adds the seasonal equation of time (±16 min). Rat-hour rule (23:00–00:59)Only matters if you were born between 23:00 and 23:59. Under the late rule the Day pillar stays on the same day and the hour stem follows the next day. Most modern practitioners use the early Rat-hour rule.

Why does birth time need correcting? ▾

Solar time, not clock time. In BaZi the hour pillar, and the day pillar near midnight, follow where the Sun actually was. Clock time is set for a whole time zone, so at your birthplace the Sun may cross the meridian earlier or later than clock noon. We use the longitude of your birthplace to correct for that, and can also add the equation of time (from −14 min in February to +16 min in November).

Daylight saving time is taken from your browser’s time zone database for the birth date, so summer-time births are converted to standard time automatically.

Whichever basis you pick, the “Pillars under each time basis” panel shows every combination side by side. If they differ, choose the one closest to the time on your birth certificate.

Remember my birth details on this device

Everything is calculated in your browser. Your details are never sent to a server; if “Remember” is on they are kept only in this browser’s storage. Privacy policy ·

About biorhythms

Biorhythm theory, popular in the 1970s, holds that three cycles start at birth: a 23-day physical cycle, a 28-day emotional cycle and a 33-day intellectual cycle. This page draws your three curves around today and shows where each one stands.

How it is calculated

Each cycle is a sine wave counted from your date of birth, so the calculation is exact: today’s value depends only on how many days you have lived. Fate Hall shows today’s percentages, the days ahead, and, on the Compatibility page, how two people’s cycles line up.

An honest note

Scientific studies have not found evidence that biorhythms predict performance, accidents or mood. Enjoy the curves as a playful calendar, not as health guidance.

Reading the curves

Values above zero are traditionally read as high phases and values below as recovery phases. The days when a curve crosses the middle line are called critical days. On the Compatibility page, two people’s curves are compared to show how closely their rhythms run together.