Ten year seasons
The word 대운 daeun is usually translated as great luck, and the translation oversells it. A luck pillar is a ten year period with its own stem and branch, which means its own elements and ten gods. Readers treat it as the weather of a decade: which parts of your chart are fed, which are pressured, which wake up.
The site shows your luck pillars as a row of tiles with the age each one starts, and outlines the one you are in now. Hover or tap for the pillar's name.
Forward or backward
Luck pillars start from your month pillar and walk along the sixty cycle. The direction follows a traditional rule that pairs the polarity of the year stem with the sex recorded at birth. A yang year stem (甲 丙 戊 庚 壬) with a male chart, or a yin year stem (乙 丁 己 辛 癸) with a female chart, goes forward. The other two combinations go backward.
This binary rule is how the classical method works, and we say so plainly. We ask for the sex recorded at birth only to set this direction, and the rest of the chart does not use it. If you would rather skip it, the calculator still shows everything else.
When they start
The starting age comes from the solar terms. For a forward chart, count the time from your birth to the next jeol (the solar term that opens the next month). For a backward chart, count back to the jeol that opened your birth month. Then divide by three: three days of that gap equal one year of age, one day equals four months, and two hours equal ten days.
Korean practice rounds this to a whole number from 1 to 10, the 대운수 daeunsu. We show both: the traditional number and the exact age in years and months, measured from birth. Some schools count the switch by Korean age or by the solar new year instead; that can move the change by up to a year either way.
Reading the current pillar
Start with the pillar's stem: what is its ten god for your day master? A Mentor decade is read as support and learning, a Challenger decade as pressure and growth, a Maker decade as output and enjoyment. Then look at the branch, which is often read as the stronger influence in the second half of the ten years, and at whether it clashes or combines with the branches in your chart.
Luck pillars are one layer. Years add another, and the site's daily line adds a light, playful third. None of them is a forecast. They are a traditional vocabulary for noticing the seasons you move through.
Questions
Why does the calculator need my sex?
Only for the traditional direction of the luck pillars. Nothing else in the chart uses it, and you can skip it.
Why is my start age different on another site?
Sites round differently, count Korean age or international age, and use different solar term times. A difference of a year is normal.
What happens before the first luck pillar?
Before it starts, readers treat the month pillar as the current season.