24 solar terms (二十四节气) reference. Enter any year from 1901 to 2100 for the Gregorian date and time, to the minute, of all 24 terms. Computed from the sun's apparent longitude; every date from 1914 to 2100 matches the Hong Kong Observatory's published tables.
24 Solar Terms Reference (二十四节气)
How to use
Enter a year
Gregorian year 1901-2100.
View all 24 solar terms
The year in Gregorian order, from Xiaohan in early January to Dongzhi in late December.
See the times
Each term shows its Gregorian date and time to the minute, on China standard time (UTC+8); before 1929, Beijing local mean time.
Cross-reference traditional almanac
The 24 solar terms anchor traditional Chinese agriculture, TCM, and seasonal practices.
24 Solar Terms: China's Agricultural Time Anchors
The 24 solar terms (二十四节气) are the solar component of the traditional Chinese calendar — dividing the year every 15° of solar longitude, totalling 24 nodes. A complete set of twenty-four first appears in the early Han dynasty book《淮南子》(Huainanzi). Inscribed by UNESCO on the Representative List of the Intangible Cultural Heritage of Humanity in 2016.
Structure
The 24 terms alternate between 12 "Joints" (Lichun, Jingzhe, Qingming…) and 12 "Climates" (Yushui, Chunfen, Guyu…). Since the 1645 Shixian calendar the terms are equal 15° steps of longitude, so each lasts 14.71 to 15.74 days. Lichun always falls around Feb 4 (Gregorian), Summer Solstice around Jun 21, Winter Solstice around Dec 21 — day-level precision.
Uses
(1) Traditional agriculture: when to plant, harvest, prune. (2) TCM: diet + lifestyle adjusts per term. (3) Festivals: Qingming + Winter Solstice are solar-term festivals, not lunar dates. (4) Bazi: month pillars are divided by solar terms, NOT lunar months.
ASEAN Chinese
HK/Taiwan/Macau/SG/MY/ID Chinese still observe Qingming for ancestor rites, Winter Solstice tangyuan, Lichun "biting the spring" rituals. The tool helps look up exact dates for advance planning.
Solar, not lunar — which is why the dates barely move
The 24 solar terms were inscribed on UNESCO's Representative List of the Intangible Cultural Heritage of Humanity in 2016.
A solar term is a position of the sun along the ecliptic, one every 15 degrees. It has nothing to do with the moon, which is why each term stays within a day or two on the Gregorian calendar.
Not one solar term has a fixed Gregorian date: in the Hong Kong Observatory's tables for 1901–2100, seventeen of them fall on three different dates and seven on four.
The range drifts by century: Lichun falls on 3 or 4 February this century, fell on 4 or 5 February last century, and has not fallen on 5 February since 1980.
Times are computed on China standard time, 120° east. The Hong Kong Observatory publishes 240 term times for 2019–2028: this tool matches 224 to the minute and the rest within a minute. Against the Observatory's tables for 1901–2100, every date from 1914 onward is the same; six terms in 1909–1913 land a day apart, all within 25 minutes of midnight.
Before 1645 the terms divided the year into equal spans of time (平氣); after the calendar reform they became equal 15° steps of the sun's longitude (定氣). That is a change of definition, not of accuracy.
Because the instant is fixed on 120° east, readers further west are often on a different local date: over 2001–2100, about 4.5% of terms for a reader at UTC+7, about 31% in London and about 52% in New York, counting daylight saving.
In bazi astrology the month pillar changes at a solar term, not at the lunar month: the year pillar turns at Lichun, the second month at Jingzhe, and so on.
Qingming is both a solar term and a festival, and the only one of the twenty-four that is a public holiday in China.
The terms describe the climate of central China — the Hong Kong Observatory says so on its own page. In Singapore the length of the day varies by about nine minutes across the whole year, and in Jakarta the summer solstice is the shortest day.
Frequently Asked Questions
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Earth's orbital period is 365.24 days (not integer), so each solar term drifts ~6 hours yearly. After 4 years that's ~1 day, absorbed by the leap year. Hence solar-term Gregorian dates oscillate within 1-2 days.
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No. Chinese New Year is lunar 正月初一 (moon-based); Lichun is sun-based. In the Hong Kong Observatory's tables for 1901–2100 they are up to 16 days apart: in 1985 Lichun fell on 4 February and New Year on 20 February.
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Qingming for ancestor rites, Winter Solstice tangyuan, Lichun "biting the spring", Summer Solstice noodles. TCM clinics also adjust seasonal recommendations per term.
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No. Browser-local, no server calls.
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UTC+8 (Beijing/Hong Kong time). Even if you're in Europe/US, the displayed time is UTC+8.
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Lichun, Lixia, Liqiu, Lidong are "starts of the 4 seasons" in Chinese calendar. Lichun (Feb 4) is 6 weeks before Western "Spring starts March 20" — the two climate definitions differ.
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The tool shows the instant on China standard time (120° east) and converts nothing. Further west your local date often differs: over 2001–2100, about 4.5% of terms at UTC+7, about 31% in London and about 52% in New York, counting daylight saving. Convert the printed time to your own offset.
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No. The range is 1901–2100, and outside it the tool refuses rather than print an unchecked answer. Before 1929 China's calendar used Beijing local mean time (116°25′ east), and the tool does the same for those years.
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We checked against the Hong Kong Observatory. Of the 240 term times it publishes for 2019–2028, this tool matches 224 exactly and the rest within a minute. In its tables for 1901–2100, every term date from 1914 on is the same, and six in 1909–1913 differ by a day. Printed almanacs do not publish their algorithms, so they cannot be compared item by item.
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Lichun = "start of spring". Yushui = "rain water" (snow turns to rain). Jingzhe = "awakening of insects" (spring thunder). Qingming = "clear bright". Each name distils ancient Chinese nature observation.
Method & sources
How it computes
Each term is the instant the Sun's apparent geocentric longitude reaches a multiple of 15 degrees (LunisolarKernel.solarTerms: truncated VSOP87 with nutation and aberration), on UTC+8 from 1929 and Beijing local mean time (UTC+7:45:40) before. Printed to the minute. Tested against HKO's published term times 2019-2028 (224 of 240 exact, all within a minute) and every term date in HKO's 1901-2100 tables.
What this tool implements
- Corrected: Purple Mountain Observatory almanac claims removed (not read); '164 of 168 HKO instants' replaced with the kernel's measured 224 of 240; Lichun vs Chinese New Year up to 16 days, not 15 (1985); local-date mismatch shares recomputed with daylight saving (UTC+7 4.5%, London about 31%, New York about 52%, 2001-2100); origin and term lengths per the UNESCO Hong Kong Association article (Huainanzi; 1645 Shixian calendar; 14.71-15.74 days).
Sources
- Hong Kong Observatory. The 24 Solar Terms: twelve major and twelve minor terms, 15 degrees of the Sun's longitude apart, vernal equinox at 0 degrees. https://www.hko.gov.hk/en/gts/time/24solarterms.htm
- Hong Kong Observatory. Date and Time of the 24 Solar Terms, Hong Kong Time (UTC+8), from HM Nautical Almanac Office and US Naval Observatory data; annual files 2019-2028. https://www.hko.gov.hk/en/gts/astronomy/Solar_Term.htm
- Hong Kong Observatory. Gregorian-Lunar Calendar Conversion Tables, 1901-2100, solar-term dates. https://www.hko.gov.hk/en/gts/time/conversion.htm
- UNESCO. The Twenty-Four Solar Terms, knowledge in China of time and practices developed through observation of the sun's annual motion. Inscribed 2016 (11.COM 10.b.6). https://ich.unesco.org/en/RL/the-twenty-four-solar-terms-knowledg…
- UNESCO Hong Kong Association. The 24 Solar Terms (April 2017): first complete set in the Huainanzi; equal 15-degree steps from the 1645 Shixian calendar, 14.71 to 15.74 days each. https://unesco.hk/archive/2017Apr/en/A4.html
- State Council of the People's Republic of China. National Annual Festivals and Memorial Days Holiday Regulation (Order No. 795, in force 1 January 2025): Qingming, one day. https://www.gov.cn/zhengce/content/202411/content_6986380.htm
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