How to read the perpetual calendar

The perpetual calendar (manse-ryeok) maps every solar/lunar date to its sixty-jiazi stem-branch. From it you derive your saju.

Pillar derivation order

Year (from li-chun), month (from solar terms), day (table lookup), hour (twelve branches). Zi-shi traditionally starts at 23:00.

Why solar terms matter

The myeongni year starts at li-chun (≈Feb 4), not Jan 1 or lunar new year. Births before li-chun use the previous year’s pillars.

Common pitfalls

Differences across sites: zi-shi convention, true solar time correction, lunar conversion edge cases. Cross-check on two.