Why Your Saju Year Might Not Match Your Birth Year
People born in January or early February are often surprised by their Saju chart: the year pillar belongs to the previous year. This is not a mistake. Saju does not start the year on January 1, and it does not start it at Lunar New Year either.
The Saju year begins at Ipchun
Ipchun (입춘, 立春), “the start of spring”, is one of the twenty-four solar terms, the points that divide the sun’s yearly path into equal steps. It falls on February 3, 4 or 5 depending on the year. In Saju the new year, with its new stem, branch and zodiac animal, begins at the exact minute of Ipchun.
In 2024, for example, Ipchun arrived on February 4 at about 5:27 p.m. Korean time. A baby born in Seoul that morning belongs to the Year of the Rabbit (癸卯); one born that evening belongs to the Year of the Dragon (甲辰).
Three different “new years”
| System | Year changes on | Used for |
|---|---|---|
| Calendar year | January 1 | Everyday dates |
| Lunar New Year (설날) | Late January to mid-February | The holiday, and the animal year in everyday talk |
| Ipchun | Around February 4 | Saju charts |
So someone can be a Dragon in conversation and a Rabbit in their Saju chart. If you were born between January 1 and about February 4, check your chart on the home page rather than a zodiac table.
Months work the same way
Saju months do not start on the first of the month. Each begins at a solar term:
| Saju month | Begins at | Usually around |
|---|---|---|
| 寅 Tiger month | Ipchun (입춘, 立春) | February 4 |
| 卯 Rabbit month | Gyeongchip (경칩, 驚蟄) | March 6 |
| 辰 Dragon month | Cheongmyeong (청명, 淸明) | April 5 |
| 巳 Snake month | Ipha (입하, 立夏) | May 6 |
| 午 Horse month | Mangjong (망종, 芒種) | June 6 |
| 未 Goat month | Soseo (소서, 小暑) | July 7 |
| 申 Monkey month | Ipchu (입추, 立秋) | August 8 |
| 酉 Rooster month | Baengno (백로, 白露) | September 8 |
| 戌 Dog month | Hallo (한로, 寒露) | October 8 |
| 亥 Pig month | Ipdong (입동, 立冬) | November 7 |
| 子 Rat month | Daeseol (대설, 大雪) | December 7 |
| 丑 Ox month | Sohan (소한, 小寒) | January 6 |
The dates shift by a day in either direction from year to year. Someone born on August 7 and someone born on August 9 can have different month pillars.
Why time zones matter
A solar term is a single instant for the whole planet, so the local clock time differs by place. That is why this site asks for the time zone of your birthplace. For most birthdays it changes nothing. It matters only if you were born within a few hours of a solar term.
Born on a boundary day?
If your birthday falls on a solar term day and you do not know your birth time, your month pillar could be either of two. A few idols on this site are in that position, and their pages say so. The guide to unknown birth times explains what still holds.
Saju is a cultural tradition, and this site treats it as entertainment. There is no scientific evidence that a birth chart determines personality or predicts the future.