Winter Solstice (Dongzhi 冬至): dates, pentads and meaning
The Sun is overhead at the Tropic of Capricorn: the shortest day and longest night in the Northern Hemisphere. The ancients said "at the winter solstice, yang is born," since the days start growing longer from here. In Taiwan people eat tangyuan (glutinous rice balls) at the winter solstice, and there is a saying that eating them makes you one year older.
Winter Solstice dates, 2026–2035
| Year | Date | Time (Taiwan, UTC+8) | Month pillar |
|---|---|---|---|
| 2026 | December 22 | 04:50 | still Geng-Zi 庚子 month |
| 2027 | December 22 | 10:42 | still Ren-Zi 壬子 month |
| 2028 | December 21 | 16:19 | still Jia-Zi 甲子 month |
| 2029 | December 21 | 22:14 | still Bing-Zi 丙子 month |
| 2030 | December 22 | 04:09 | still Wu-Zi 戊子 month |
| 2031 | December 22 | 09:55 | still Geng-Zi 庚子 month |
| 2032 | December 21 | 15:55 | still Ren-Zi 壬子 month |
| 2033 | December 21 | 21:46 | still Jia-Zi 甲子 month |
| 2034 | December 22 | 03:34 | still Bing-Zi 丙子 month |
| 2035 | December 22 | 09:30 | still Wu-Zi 戊子 month |
Times computed by our calendar code (UTC+8); they agree with an astronomical calculation to within about a minute. Between 1901 and 2100, Winter Solstice always falls on December 21–23. Subtract 8 hours for UTC.
The three pentads of Winter Solstice
| Sign of the season | When | |
|---|---|---|
| First pentad | Earthworms curl up (蚯蚓結) | about days 1–5 after Winter Solstice |
| Second pentad | Elk shed their antlers (麋角解) | about days 6–10 after Winter Solstice |
| Third pentad | Springs begin to flow (水泉動) | about days 11–15 after Winter Solstice |
The ancients split each solar term into three pentads (hou 候) of about five days each, and marked them by changes in birds, animals and plants: seventy-two pentads a year. These follow the standard list in Wu Cheng's Yuan-dynasty Collected Explanations of the Seventy-Two Pentads. They were observed in the Yellow River basin, so they do not always match what you see in Taiwan, let alone elsewhere. Some, like hawks turning into doves, record old beliefs rather than biology.
Winter Solstice in the sky: where the Sun is
The solar terms follow the Sun along the ecliptic: one term for every 15°, and Winter Solstice is the moment the Sun reaches longitude 270°. In 2027, at Winter Solstice the Sun sits against the stars of Sagittarius (drowned out by daylight, of course). That day in Taipei the Sun rises at 06:34 and sets at 17:09, about 10 h 35 min of daylight.
What Winter Solstice means in BaZi
Winter Solstice is a qi (氣), or "middle term" (中氣): it falls in the middle of the Zi month (子), so the BaZi month pillar does not change here; it is the same Zi month before and after. Middle terms matter in the calendar for another reason: a lunar month with no middle term in it becomes the leap month.
BaZi months are not counted from the lunar new moon but from the jie terms: Start of Spring, Awakening of Insects, Pure Brightness, Start of Summer, Grain in Ear, Minor Heat, Start of Autumn, White Dew, Cold Dew, Start of Winter, Major Snow and Minor Cold each open a month. If you were born on the day of a jie term, within a few hours of it, your month pillar (and for the Start of Spring, your year pillar too) can shift by one; it depends on the exact time. See solar term boundaries, and for how the month's heavenly stem is worked out, the month pillar.
Customs
An old saying held that "the winter solstice is as big as New Year." The Zhou dynasty once began its year with the Zi month that contains the solstice, but BaZi still changes the year at the Start of Spring.
Look up the solar terms for any year
Pick a year to list the exact time of all 24 solar terms (Taiwan time, UTC+8) and the month pillar each jie term starts. Add a month and day, such as a birthday, to see which solar-term period it falls in and its month pillar. Everything is calculated in your browser.
The times come from the same calendar code our BaZi charts use; for 1901–2100 they agree with an astronomical calculation to within about a minute. If you were born within minutes of a term changing, see solar term boundaries.
The terms before and after
The previous term is Major Snow; the next is Minor Cold.
A straight word: solar terms are astronomy; luck is something else
The twenty-four solar terms divide the year by the Sun's position on the ecliptic, and their times can be computed to the second. BaZi uses them to change the year and the month; that is a rule of calculation. A solar term carries no good or bad luck of its own, and no term is a "better" one to be born in: a chart is read as a whole, by its Five Elements and Ten Gods. Everything on this site is for reference and entertainment.
Solar terms set the month; the month sets strength
Enter your birth date for a free Four Pillars chart and see your month element and the balance of your whole chart.
Winter Solstice: common questions
What date is Winter Solstice in 2026?
In 2026, Winter Solstice falls on December 22 at 04:50 Taiwan time (UTC+8); in 2027 it is December 22 at 10:42.
Why does Winter Solstice move from year to year?
A solar term is the moment the Sun reaches a set longitude, here 270°. A year is about 365.24 days, not a whole number, and leap years reset the count, so the date drifts within a few days. From 1901 to 2100, Winter Solstice always falls on December 21–23.
What are the three pentads of Winter Solstice?
First: Earthworms curl up (蚯蚓結); second: Elk shed their antlers (麋角解); third: Springs begin to flow (水泉動). They follow the standard Yuan-dynasty list.
What does Winter Solstice do in a BaZi chart?
It is the middle term of the Zi month, so the month pillar does not change. BaZi changes months only at the jie terms.