Every character in a saju chart is a combination drawn from 10 Heavenly Stems (천간) and 12 Earthly Branches (지지). The Stems represent the energy of heaven, the Branches represent the energy of earth, and together they form each pillar.
The 10 Heavenly Stems are: Gap (甲), Eul (乙), Byeong (丙), Jeong (丁), Mu (戊), Gi (己), Gyeong (庚), Sin (辛), Im (壬), and Gye (癸). Each pair maps to one of the Five Elements — Gap and Eul are Wood, Byeong and Jeong are Fire, Mu and Gi are Earth, Gyeong and Sin are Metal, Im and Gye are Water. Odd-numbered Stems are Yang; even-numbered Stems are Yin.
Each Stem carries a vivid metaphor that makes its energy tangible. Gap is the towering tree — upright leadership. Eul is the vine — graceful flexibility. Byeong is the blazing sun — radiant warmth. Jeong is the candle — focused intensity. Mu is the mountain — steadfast reliability. Gi is the cultivated field — humble productivity. Gyeong is the boulder — resolute strength. Sin is the jewel — precise refinement. Im is the ocean — vast wisdom. Gye is the morning dew — quiet nurturing power.
The 12 Earthly Branches are: Ja (子), Chuk (丑), In (寅), Myo (卯), Jin (辰), Sa (巳), O (午), Mi (未), Sin (申), Yu (酉), Sul (戌), and Hae (亥). These correspond to the 12 zodiac animals familiar to many — Rat, Ox, Tiger, Rabbit, Dragon, Snake, Horse, Sheep, Monkey, Rooster, Dog, and Pig.
The Branches are more complex than the Stems because each one contains hidden Stems called 'jijanggwan' (지장간). For instance, In (寅, Tiger) conceals Gap (甲), Byeong (丙), and Mu (戊) within it, while Chuk (丑, Ox) hides Gi (己), Gye (癸), and Sin (辛). These hidden Stems add layers of depth to Branch interpretation, making the subconscious landscape of a chart far richer than it first appears.
While the Heavenly Stems reveal outer, conscious tendencies, the Earthly Branches expose inner, subconscious inclinations. For example, someone whose Day Stem is Byeong (丙, Yang Fire) appears bright and passionate, but if their Day Branch is Ja (子, Yang Water), a calm and observant nature lies beneath the surface.
Consider how this plays out in real life. You may know a colleague who radiates energy and enthusiasm at work — that is the Stem speaking. Yet after hours, they crave solitude and quiet reading — that is the Branch revealing a Water-influenced inner world. The gap between how someone presents outwardly and what they need inwardly is often a Stem-Branch story.
When Stems and Branches combine, they produce 60 unique pairings known as the Sexagenary Cycle (60갑자). Starting from Gap-Ja (甲子) and ending at Gye-Hae (癸亥), these 60 combinations are assigned to the year, month, day, and hour to create each person's one-of-a-kind energy blueprint.
Why 60 combinations and not 120 (10 times 12)? Because Yang Stems only pair with Yang Branches, and Yin Stems only pair with Yin Branches. This halves the total, producing exactly 60 unique combinations. In Korean tradition, the 60th birthday — called hwangap (환갑) — celebrates the completion of one full Sexagenary Cycle, symbolizing a cosmic return to the energy configuration of one's birth year.
The interactions between Stems and Branches — harmonies, clashes, punishments, and more — are what give saju its analytical power. DESTIGER automatically decodes these intricate relationships, reading your energy structure as clearly as an astronomer charts the constellations.
To understand how these relationships work in practice, consider the concept of Heavenly Stem Combinations (천간합). When certain pairs of Stems meet, they attract each other and transform into a new element entirely. Gap and Gi combine to form Earth; Eul and Gyeong produce Metal; Byeong and Sin create Water; Jeong and Im yield Wood; Mu and Gye generate Fire. When such a combination exists within a chart, the energies of those characters may shift from their original element, meaning the surface-level elemental distribution can be misleading. Skilled saju practitioners — and DESTIGER's algorithms — account for these transformations to deliver a more accurate reading of your true energy profile.
Earthly Branch Clashes (지지충) are another critical dynamic. There are six clash pairs — Ja-O, Chuk-Mi, In-Sin, Myo-Yu, Jin-Sul, and Sa-Hae — each representing opposing energies that collide when they appear together. Clashes are often misunderstood as purely negative, but they can serve as powerful catalysts for change. Someone stuck in a stagnant career might experience a clash year that shakes loose the inertia and pushes them toward a long-overdue transition. The key is awareness: when you know a clash is active in your chart or fortune cycle, you can channel that turbulent energy constructively rather than being caught off guard.
A practical example helps illustrate the layered nature of Stems and Branches. Imagine two colleagues, both born in a Dragon year (辰, Jin). On the surface, they share the same Earthly Branch for their year pillar. But one has a Gap (甲) Heavenly Stem above the Dragon, making them a Yang Wood Dragon, while the other has a Mu (戊) Stem, making them a Yang Earth Dragon. The Wood Dragon is an innovator — always pushing for growth and new ideas — while the Earth Dragon is a stabilizer — focused on structure, reliability, and long-term planning. Same animal sign, profoundly different energy expression. This is why pop-culture horoscopes based solely on birth year are far too simplistic; the full eight-character chart is essential for meaningful insight.
People often ask: 'How do I find out my own Heavenly Stems and Earthly Branches?' Traditionally, you would consult a Ten-Thousand-Year Calendar (만세력) — a reference book mapping every date in history to its corresponding Stem-Branch pair. Today, digital platforms like SAJUVERSE make this effortless: enter your date and time of birth, and the system instantly generates your complete eight-character chart. DESTIGER goes further by automatically analyzing every relationship among your Stems and Branches — combinations, clashes, punishments, destructions, and harms — and presenting the results in intuitive visual charts with clear explanations, so you can understand your cosmic blueprint without years of study.