Understanding the 60-year cycle (육십갑자) that forms the foundation of Korean timekeeping and Saju analysis.
At the mathematical heart of Korean Saju lies the sexagenary cycle (육십갑자, Yuksip-gapja) — a 60-year repeating sequence created by combining the 10 Heavenly Stems with the 12 Earthly Branches. This elegant system has been used in Korea for timekeeping, fortune telling, and cultural practices for over a millennium, and it remains the foundational clock of all Saju calculations.
The cycle works through a simple but ingenious pairing mechanism. The first year pairs the first Stem (甲, Gap) with the first Branch (子, Ja), creating 甲子 (Gapja). The second year pairs the second Stem (乙, Eul) with the second Branch (丑, Chuk), creating 乙丑 (Eulchuk). This continues until all possible combinations are exhausted after 60 pairs — since 10 and 12 share a least common multiple of 60.
Each of the 60 Stem-Branch combinations has a unique energetic signature. 甲子 (Gapja) — Yang Wood on Rat — carries very different energy from 乙丑 (Eulchuk) — Yin Wood on Ox. Saju practitioners memorize or reference the qualities of all 60 combinations, understanding the specific interaction between each Stem and its paired Branch. Some combinations are considered particularly auspicious, while others present specific challenges.
Published: 2026-01-22
Interactive fortune reading is available with JavaScript enabled.