Chinese Lunar Calendar Explained

What the Chinese Lunar Calendar Is

The Chinese lunar calendar tracks months by the phases of the moon, while the Western calendar follows the solar year. Lunar months begin at the new moon and run about 29 to 30 days.

Because 12 lunar months add up to fewer days than a solar year, some years include a leap month to keep the seasons aligned.

Diagram comparing lunar months and the solar year
Lunar months follow moon phases and occasionally add a leap month.

How Lunar Age Is Calculated

Lunar age starts at one at birth and increases at each Chinese New Year. This means your lunar age can be one or two years ahead of your Western age depending on your birthday timing.

  1. Start at age one when you are born.
  2. Add one year at every Chinese New Year.
  3. Compare your birthday to that year's New Year to find the current lunar age.
Birth DateDate of Conception YearLunar Age
May 5, 1994June 202633
January 10, 1994June 202634

Try the lunar age calculator for an exact conversion.

Why Lunar Months Matter in the Chinese Gender Calendar

The Chinese gender calendar uses lunar months because the chart was built around lunar timekeeping. Converting the conception date correctly is essential for matching the right column.

If you want to see the method end to end, start with the chinese gender calendar calculator and then review the full chart logic.

Flow diagram from Gregorian date to lunar month and chart lookup
Lunar month conversion is the bridge between a Western date and the chart.

Common Lunar Calendar Confusion

Western birthdays do not map cleanly to lunar ages because the lunar year starts on a different date each year.

Leap months can shift the numbering of lunar months, which is why automated conversion is helpful.

For a deeper guide on the chart itself, see the chinese gender chart overview. For common questions, visit the FAQ.