1. Core Concept (核心概念)
Nong Li (农历)—literally the “agricultural calendar”—is the traditional Chinese calendar. Despite the common English name “lunar calendar,” it is technically a lunisolar calendar (阴阳历): its months track the moon’s phases, while its years stay aligned with the solar cycle through intercalation.
The system was fully refined by the Han Dynasty (206 BCE–220 CE) and remained China’s official calendar until 1912. Today it still determines the dates of every major traditional festival, ancestral rites, deity birthdays, and the timing of lucky-day selection (择吉日).
- Month rule: Each month begins on the day of the new moon (朔, Shuò); the 15th day of the month falls on the full moon (望, Wàng).
- Year rule: A normal year has 12 months (≈354 days), a leap year has 13 months (≈384 days).
2. Months and Moon Phases (月份与月相)
The lunar month (朔望月, Shuò Wàng Yuè) averages 29.53 days, so calendar months alternate between 29 days (“small month” 小月) and 30 days (“big month” 大月). The month numbering follows the Earthly Branch system, with the first month (正月, Zhēng Yuè) anchored to the month containing the start of spring.
| Moon Phase | Term | Lunar Date | Cultural Moment |
|---|---|---|---|
| New Moon | 朔 (Shuò) | Day 1 | Month begins; temple offerings |
| First Quarter | 上弦 (Shàng Xián) | ~Day 7–8 | — |
| Full Moon | 望 (Wàng) | Day 15 | Lantern Festival, Mid-Autumn moon gazing |
| Last Quarter | 下弦 (Xià Xián) | ~Day 22–23 | — |
| Dark Moon | 晦 (Huì) | Last day | Month closes; settling accounts |
3. Keeping Pace with the Sun: Leap Months (闰月)
Twelve lunar months total only about 354 days—roughly 11 days short of the solar year. Without correction, festival dates would drift through the seasons. The solution: a leap month (闰月, Rùn Yuè) is inserted roughly every 2–3 years.
The Metonic Rule (十九年七闰)
Over a 19-year cycle, 7 leap years keep the calendar synchronized with the seasons. A leap year duplicates one month (e.g., “Leap Fifth Month” 闰五月), which is why some festivals occasionally occur twice in a single Gregorian year.
The Solar-Term Anchor
Leap months are placed scientifically: the month without a major solar term (中气) becomes the leap month. This anchors the calendar to the 24 Solar Terms, the solar backbone that farmers still use to schedule sowing and harvest.
4. The 60-Year Cycle (干支纪年)
Calendar years are named by pairing 10 Heavenly Stems with 12 Earthly Branches, producing a repeating 60-year cycle (六十甲子). Each year’s name also encodes its element and zodiac animal—for example, 2026 is Bing-Wu (丙午), a Fire Horse year beginning on February 17, 2026.
This naming system is essential for:
- Fortune-telling (八字命理): the stem-branch pairs of one’s birth year, month, day, and hour.
- Deity birthdays: temples schedule celebration dates by the traditional calendar.
- Anniversaries: the 60th birthday (花甲, Huā Jiǎ) marks a full life cycle and is celebrated as a major milestone.
5. Festival Dates on the Lunar Calendar (节日日期)
Almost all major traditional festivals are fixed to lunar dates, which is why their Gregorian dates shift every year:
| Festival | Lunar Date | Gregorian Date (2026) |
|---|---|---|
| Spring Festival (春节) | 1st month, day 1 | February 17 |
| Lantern Festival (元宵节) | 1st month, day 15 | March 3 |
| Dragon Boat Festival (端午节) | 5th month, day 5 | June 19 |
| Qixi Festival (七夕) | 7th month, day 7 | August 19 |
| Hungry Ghost Festival (中元节) | 7th month, day 15 | August 27 |
| Mid-Autumn Festival (中秋节) | 8th month, day 15 | September 25 |
| Double Ninth Festival (重阳节) | 9th month, day 9 | October 18 |
The Ghost Month (鬼月)
The entire seventh lunar month is considered the month of wandering spirits. Weddings and major moves are traditionally avoided, while families burn joss paper to honor ancestors—customs rooted in the lunar calendar’s spiritual rhythm.
6. Living Calendar (活的传统历)
Even in modern China, the lunar calendar remains a living system:
- Birth dates: many people celebrate traditional birthdays by the lunar date.
- Auspicious days (黄道吉日): weddings, business openings, and housewarmings are scheduled by lunar-calendar almanacs (黄历, Huáng Lì).
- Festival countdowns: the question “How many days to New Year?” is always answered in lunar terms—“the year ends on 除夕 (Chú Xī), the last day of the twelfth month.”