What Is Daewoon? The 10-Year Cycles in a Saju Chart

A daewoon is one stem-branch pair governing roughly ten years, derived from the Month Pillar and read against the natal chart rather than scored.

Daewoon (대운, 大運) is the sequence of ten-year cycles in a Saju chart. Each cycle is one stem-branch pair from the sixty-pillar calendar, and the sequence starts from the Month Pillar and runs either forward or backward through that calendar. The first cycle begins at a calculated age, usually somewhere between one and ten. A daewoon adds two characters to the natal eight. It replaces none of them.

Where the sequence comes from

The Month Pillar is the seed. Every daewoon is the pillar that sits some number of steps before or after it in the sixty-pillar cycle, the same cycle that names 2026 丙午 Byeong-O and 2027 丁未 Jeong-Mi.

Direction is the first decision. The traditional convention pairs the Year Stem's polarity with the person's sex: a male born in a yang-stem year (甲, 丙, 戊, 庚, 壬) counts forward, and so does a female born in a yin-stem year (乙, 丁, 己, 辛, 癸). The other two combinations count backward. That is the traditional convention, and it is what most Korean manseryeok tables apply by default. Some modern practitioners question a sex-based direction rule and compute both sequences, or use the polarity of the Year Stem alone. We state the traditional convention here because it is what a reader is most likely to meet, and we flag the disagreement because it is real.

The start age is the second decision. Count the days from the birth moment to the next solar term (절기, 節氣) if the sequence runs forward, or back to the previous solar term if it runs backward. Divide by three. Three days equal one year of starting age, one day equals four months, and two hours equal ten days. Schools differ on how to round the remainder.

A worked example: July 20, 2026, Seoul

Take a birth at 10:00 am on July 20, 2026 in Seoul. The year is 丙午 Byeong-O, so the Year Stem is 丙 Byeong, a yang stem. The month is the Mi 未 month, which began at Soseo (소서, 小暑) on July 7, 2026 at 10:56 KST and ends at Ipchu (입추, 立秋) on August 7, 2026 at 20:42 KST. The Month Pillar is 乙未 Eul-Mi.

A male with this birth counts forward, toward Ipchu:

July 20, 10:00 to August 7, 20:42 is 18 days, 10 hours and 42 minutes.
18 days ÷ 3 = 6 years.
The remaining 10 hours and 42 minutes are about 0.15 of a year, roughly two months.
The first daewoon begins at about age 6.

A female with the same birth counts backward, toward Soseo:

July 7, 10:56 to July 20, 10:00 is 12 days, 23 hours and 4 minutes.
12 days ÷ 3 = 4 years.
The remaining 23 hours are about 0.32 of a year, close to four months.
The first daewoon begins at about age 4 years 4 months, which most tables print as 4 or 5 depending on their rounding.

Two births at the same moment, eight identical natal characters, and the cycles begin two years apart and run in opposite directions. Whether the printed number is a Korean age or a completed-years age is a display convention. Ask which one a table uses before comparing it to your own.

The first four cycles for that example

Cycle	Forward (male, yang year)	Approximate ages	Backward (female, yang year)	Approximate ages
1st	丙申 Byeong-Sin	6 to 15	甲午 Gap-O	4 to 13
2nd	丁酉 Jeong-Yu	16 to 25	癸巳 Gye-Sa	14 to 23
3rd	戊戌 Mu-Sul	26 to 35	壬辰 Im-Jin	24 to 33
4th	己亥 Gi-Hae	36 to 45	辛卯 Sin-Myo	34 to 43

乙未 Eul-Mi is pillar 32 of 60. Forward, the sequence walks to 33, 34, 35, 36. Backward, it walks to 31, 30, 29, 28. Nothing in the natal chart changed between the two columns. The Month Pillar and the direction rule did all the work.

How a daewoon is read

A daewoon is a new stem and a new branch placed beside the natal chart for about a decade. The reader asks what those two characters are to the Day Master (일간, 日干, ilgan), and the answer is a Ten Gods label. For a Gap 甲 Wood Day Master, the 丙申 cycle brings a 丙 stem that is Output (Siksin) and a 申 branch whose main hidden stem 庚 is Power (Pyeongwan). For a Gyeong 庚 Metal Day Master, the same 丙 stem is Power and the same 申 branch is Companion. Same cycle, different reading, because the reference point differs.

The cycle also interacts with the natal branches directly. A 申 daewoon branch meets a natal 寅 branch as a clash, a natal 子 or 辰 branch as part of a three-way combination. Those are structural relationships. They shift which elements have support and which are under pressure, and they change which Ten Gods are prominent for the period. None of that is a score.

There is a further convention that splits each cycle in two: the stem is weighted for roughly the first five years and the branch for the second five. Some schools read the branch across all ten years and treat the stem as a modifier. Others weight both throughout. When two readers describe the same decade differently, this is often the reason.

Why Kairo does not promise a good ten years

"A good daewoon" compresses a two-character relationship into a verdict, and the tradition itself resists that compression. A cycle that brings Wealth to a Day Master with no outlet reads differently from one that brings Wealth to a Day Master already surrounded by it. A Power cycle reads as structure for one chart and as constraint for another.

Kairo reads a daewoon as a change of conditions. The question we put to the reader is how the same chart responds when the conditions around it move, and that response is observable in a way a fortune label is not.

Pattern questions for a cycle boundary

If a table shows that you changed daewoon within the last three years, test the change against the record rather than the label:

Which strategy that worked reliably for the previous decade has stopped producing the same result since the boundary?
Did a source of support shift, such as a mentor, an institution, a client or a market, without you changing your approach?
Are you meeting the same kind of pressure in a new form, or a new kind of pressure altogether?
Which decision from the past two years would you have made differently five years earlier, and why?

If none of the answers move, the cycle label is not describing anything you can use yet.

What this can and cannot tell you

The arithmetic above is exact given the birth moment, the solar-term timestamps and a stated rounding rule. Kairo flags a birth within a day or so of a solar-term boundary as uncertain, because a two-hour error there shifts the start age by ten days and a one-day error shifts it by four months. Without a birth time, the start age carries up to four months of uncertainty and we say so instead of guessing.

Everything after the arithmetic is interpretation. Saju is an interpretive tradition, not a validated predictive method, and we don't present it as one. A daewoon table tells you which two characters sit beside your chart for a decade, and nothing in the table records what you did with the last one.