The 24 solar terms —
the calendar behind a saju chart

How the twenty-four are made

Seen from Earth, the Sun moves once around the sky each year. Divide that circle into 24 equal arcs of 15 degrees and you have the solar terms: the moment the Sun reaches 315° is the Start of Spring, 0° is the spring equinox, 90° the summer solstice, and so on. Because the Sun moves a little faster in winter, when Earth is nearest to it, the terms are not spaced perfectly evenly in time — about 14.7 days apart in January, 15.7 in July — but each falls within a day or two of the same Western date every year.

The twenty-four alternate between two kinds. The jie (절, 節, “sectional terms”) begin the twelve solar months; the zhongqi (중기, 中氣, “middle terms”) mark their midpoints, and include the two equinoxes and two solstices. In the traditional lunisolar calendar a month with no zhongqi becomes the leap month, which is how the two calendars are kept in step.

The twelve that begin the months of a chart

A saju or BaZi month runs from one jie to the next. The Tiger month, the first of the chart’s year, opens at the Start of Spring; the Ox month, the last, opens at Minor Cold in January. Each month carries one of the twelve earthly branches, the same characters as the zodiac animals.

Nothing changes at a zhongqi, so a birth on the day of a solstice or an equinox needs no special care. A birth on the day of a jie does: the month pillar depends on whether the birth came before or after the exact time, and the yearly pages below give that time to the minute.

The year begins at Ipchun

The Start of Spring, Ipchun (입춘) in Korean and Lichun in Chinese, is the saju New Year. The year pillar and the month pillar change together at that moment, which falls on February 3, 4 or 5 depending on the year. This is different from Lunar New Year, which the popular zodiac uses and which can fall anywhere from January 21 to February 20; it is why a January baby is always the previous year’s animal in a chart. The Ipchun guide explains the rule and its edge cases.

Dates and times by year

• 24 solar terms of 2026 — Ipchun Feb 4 at 05:02, winter solstice Dec 22 at 05:50 (KST)
• 24 solar terms of 2027 — Ipchun Feb 4 at 10:46, winter solstice Dec 22 at 11:42 (KST)
• 24 solar terms of 2028 — Ipchun Feb 4 at 16:31, winter solstice Dec 21 at 17:20 (KST)

Times are Korea Standard Time as published by the Korea Astronomy and Space Science Institute, with UTC alongside. Beijing and Hong Kong run one hour behind Korea.

The twenty-four terms explained

In calendar order, with the Chinese pinyin and Korean names. The dates are the range across 2026–2028.

• Minor Cold 小寒 Xiaohan · Korean sohan · around Jan 5–6 · opens the Ox month
  Despite the name, usually the coldest stretch of the Korean year. The Ox month opens: the last month of the saju year, frozen ground where plans are made.
• Major Cold 大寒 Dahan · Korean daehan · around Jan 20
  The last of the twenty-four. “Great cold” by name, but spring is close: the saju year ends at the next term.
• Start of Spring 立春 Lichun · Korean ipchun · around Feb 4 · opens the Tiger month
  The saju New Year. At this moment the year pillar and the month pillar change together, and so does the zodiac animal in a chart. Korean households paste 立春大吉 on the door.
• Rain Water 雨水 Yushui · Korean usu · around Feb 19
  Snow turns to rain and the ice begins to melt. What was frozen, in the fields and in plans, starts to loosen.
• Awakening of Insects 驚蟄 Jingzhe · Korean gyeongchip · around Mar 5–6 · opens the Rabbit month
  Hibernating creatures stir and frogs come up from the ground. The Rabbit month opens, the gentlest month of Wood.
• Spring Equinox 春分 Chunfen · Korean chunbun · around Mar 20–21
  Day and night are equal as the Sun crosses the celestial equator heading north. From here the days grow longer than the nights.
• Clear and Bright 清明 Qingming · Korean cheongmyeong · around Apr 4–5 · opens the Dragon month
  Clear skies and the start of the farming year. Qingming is tomb-sweeping day in China; Korea’s Hansik (한식), a day for tending family graves, falls beside it.
• Grain Rain 穀雨 Guyu · Korean gogu · around Apr 19–20
  The rain that fattens the grain. Rice seedbeds are prepared, and it is the last term of spring.
• Start of Summer 立夏 Lixia · Korean ipha · around May 5–6 · opens the Snake month
  Summer begins in the calendar, weeks before it feels like it. In a saju chart the Snake month opens: the season of Fire.
• Grain Buds 小滿 Xiaoman · Korean soman · around May 20–21
  “Small fullness”: the grain fills but has not ripened. Barley turns golden and everything is still growing.
• Grain in Ear 芒種 Mangzhong · Korean mangjong · around Jun 5–6 · opens the Horse month
  Time to sow the bearded grains and transplant rice. The Horse month opens, the most yang month of the year.
• Summer Solstice 夏至 Xiazhi · Korean haji · around Jun 21
  The longest day and shortest night. The peak of light is also the turning point: from here the nights lengthen.
• Minor Heat 小暑 Xiaoshu · Korean soseo · around Jul 6–7 · opens the Goat month
  The real heat begins and the rainy season peaks. The Goat month opens, the dry Earth of late summer.
• Major Heat 大暑 Dashu · Korean daeseo · around Jul 22–23
  The hottest stretch of the year, when the monsoon ends and the heat settles in.
• Start of Autumn 立秋 Liqiu · Korean ipchu · around Aug 7–8 · opens the Monkey month
  Autumn begins in the calendar while the heat lingers. The Monkey month opens: the season of Metal, of harvest and finishing.
• End of Heat 處暑 Chushu · Korean cheoseo · around Aug 22–23
  The heat withdraws; mornings and evenings turn cool. Koreans say the mosquitoes’ mouths go crooked at Cheoseo.
• White Dew 白露 Bailu · Korean baengno · around Sep 7–8 · opens the Rooster month
  Dew forms as the nights cool. The Rooster month opens, the sharpest month of Metal.
• Autumn Equinox 秋分 Qiufen · Korean chubun · around Sep 22–23
  Day and night are equal again, and from here the nights are longer. A time for taking stock.
• Cold Dew 寒露 Hanlu · Korean hallo · around Oct 8 · opens the Dog month
  The dew turns cold. The Dog month opens, autumn’s Earth, the month of filling the storehouse.
• Frost Descent 霜降 Shuangjiang · Korean sanggang · around Oct 23–24
  The first frost. The last of the harvest comes in before the ground hardens.
• Start of Winter 立冬 Lidong · Korean ipdong · around Nov 7–8 · opens the Pig month
  Winter begins; in Korea it is kimchi-making (김장) season. The Pig month opens: the season of Water.
• Minor Snow 小雪 Xiaoxue · Korean soseol · around Nov 22
  The first light snow, and the ground begins to freeze. Preparations for winter are finished.
• Major Snow 大雪 Daxue · Korean daeseol · around Dec 6–7 · opens the Rat month
  Heavy snow. The Rat month opens, the deepest yin month of the year, when thinking runs deep and decisions slow down.
• Winter Solstice 冬至 Dongzhi · Korean dongji · around Dec 21–22
  The longest night. Koreans eat red-bean porridge (팥죽) and count the day as the return of the light.

Korea, China and Japan

The terms are the same instants everywhere; only the names and the clocks differ. Korea writes 절기 and reads the characters in Korean (입춘 Ipchun, 동지 Dongji); China writes 节气 and reads them in Mandarin (立春 Lichun, 冬至 Dongzhi); Japan writes 節気 and reads 立春 as Risshun. Korean and Japanese almanacs give the times in UTC+9, Chinese and Hong Kong almanacs in UTC+8. A few Korean customs hang on particular terms: pasting 立春大吉 on the door at Ipchun, tending family graves around Hansik near Clear and Bright, making kimchi after the Start of Winter, and eating red-bean porridge at the winter solstice.

FAQ

What is a solar term?

One of twenty-four points on the Sun’s yearly path, spaced 15 degrees apart, that East Asian calendars have used for over two thousand years to track the seasons. Each is an instant, not a day, and they arrive about 15 days apart. Korean calls them jeolgi (절기), Chinese jieqi (节气), Japanese sekki (節気).

Are solar terms lunar?

No. They follow the Sun alone, which is why they fall on almost the same Western dates every year. Lunar New Year, by contrast, moves by weeks. A saju chart uses the solar terms for its year and month pillars and never the lunar calendar.

Why does a solar term shift by a day from year to year?

The solar year is about a quarter of a day longer than 365 days, so each term arrives roughly six hours later than the year before until a leap day pulls it back. Over a few years the same term can fall on the 3rd, 4th or 5th of a month.

Which solar terms change a saju or BaZi chart?

The twelve jie: Start of Spring, Awakening of Insects, Clear and Bright, Start of Summer, Grain in Ear, Minor Heat, Start of Autumn, White Dew, Cold Dew, Start of Winter, Major Snow and Minor Cold. Each begins a solar month and changes the month pillar; the Start of Spring changes the year pillar as well.

What saju is · Day pillar calendar · Chinese lunar calendar · Lunar New Year dates · Lunar birthday calculator · 한국어: 절기