What is a leap month?

An extra lunar month inserted roughly every 2-3 years (7 times every 19 years) to keep the lunar calendar's 12 months (about 354 days) aligned with the 365-day solar year — determined by which lunar month lacks a "major" solar term that year.

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Chinese & Japanese Calendars

Chinese Calendar Converter

Convert between the Gregorian and Chinese lunisolar calendars.

🔒 Runs entirely in your browser — nothing here is ever uploaded

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About the Chinese Calendar Converter

Converts dates between the Gregorian calendar and the Chinese lunisolar calendar, in either direction.

100% Free Runs in Your Browser No Sign-Up Required

How to use it

Choose a direction: Gregorian to Chinese, or Chinese to Gregorian.
Enter the date.
Read the converted date, including the year's GanZhi (stem-branch) name and zodiac animal.

Formula

Uses the `lunar-javascript` library's real astronomical calculation — each lunar month begins on the day of an actual new moon, and a leap month is inserted roughly every 2-3 years to keep the calendar aligned with the solar year (based on the 24 solar terms).

Worked example

February 17, 2026 is Chinese New Year — 1st day of the 1st lunar month, Year of the Horse (丙午).

Interpreting your result

This is the general Chinese calendar shared by Chinese folk religion, Buddhism, and secular Chinese culture alike — not a specifically "Taoist" calendar. Verified against 2 independently-published real dates: Chinese New Year 2026 (February 17, Year of the Horse) and Mid-Autumn Festival 2026 (September 25), both matched exactly.

Recommendations

• For a leap month, enter a negative month number (e.g. -6 for a leap 6th month) — the calendar doesn't have a leap month every year, so an invalid combination will show an error.

Frequently asked questions

Because it's tied to a real new-moon occurrence (the 2nd new moon after the winter solstice), not a fixed solar-calendar date — it falls anywhere between January 21 and February 20.