Lunar new year, in full
The Chinese calendar is lunisolar. Months start at a new moon, which makes them 29 or 30 days long, and an extra month gets inserted every few years to keep the count in step with the solar year. New year day is the new moon falling between 21 January and 20 February, which in most years is the second new moon after the December solstice. The calculation uses a meridian in China, so the date can differ by a day from a local reckoning elsewhere.
Because the year turns in late January or February, a birth in that window frequently carries the previous year's animal. Someone born on 5 February 2024 is not a dragon. The dragon year did not start until 10 February 2024, so that birthday sits inside the rabbit year that began on 22 January 2023. Any rule of thumb that reads the animal straight off the Gregorian year gets these cases wrong.
The festival itself, Spring Festival in Chinese, runs about fifteen days and closes with the lantern festival at the first full moon of the year. Korea's Seollal and Vietnam's Tet mark the same turn on calendars computed slightly differently, so the dates occasionally diverge.
- Astrology
- Chinese New Year, Spring Festival
A worked example
Take a birthday of 20 January 2025. The 2025 lunar year, the snake, did not open until 29 January 2025, so that birth belongs to the dragon year that started on 10 February 2024. Nine days later, on 29 January, the same birthday would be a snake. The lookup behind this site's Chinese zodiac pages compares the birth date with the new year date rather than reading the Gregorian year.
Sources
The first day of the first lunar month fell on 22 January 2023, 10 February 2024 and 29 January 2025.
Hong Kong Observatory — Gregorian-Lunar calendar conversion tablesMonths in the Chinese calendar begin at a new moon, and leap months are inserted to keep the lunar count in step with the solar year.
Hong Kong Observatory — Information on the Chinese calendar
See also
Where it comes up on this site
Lunar new year: frequently asked
It is set by the moon rather than by the Gregorian calendar. New year day is a new moon, new moons drift against a solar year, and so the date wanders inside a window running from 21 January to 20 February.
Check the birth date against that year's lunar new year date, because the animal changes over then and not on 1 January. A birth on 8 February 2024 falls before the dragon year opened on 10 February, so it sits in the rabbit year that began on 22 January 2023. Reading the animal off the Gregorian year gets every case like this wrong.
Usually. The Chinese, Korean and Vietnamese new years descend from the same lunisolar system and mostly land on the same day, though different reference meridians can separate them by one.