Chinese calendar · Nominal age
Lunar Age Calculator
Find your Chinese age on any date. Enter your birth date and the date you want to check.
How to calculate lunar age
Lunar age = lunar year of the reference date − lunar year of birth + 1.
You are one at birth and gain a year on Lunar New Year. This calculator uses that boundary, also known as Chinese New Year. It does not use January 1 or Li Chun, the Start of Spring used in some astrology calculations.
Enter the Gregorian dates as recorded. No birth time is needed. Read the lunar age formula and examples for a step-by-step explanation.
Why the New Year boundary matters
A person born on February 1, 1995 has a lunar age of 31 on February 1, 2026. The calculation is 2025 − 1995 + 1. That is also their Western age on that date. Adding one or two to Western age would give the wrong answer.
A baby born on February 1, 2026 belongs to lunar year 2025. On February 17, 2026, Lunar New Year begins and the baby reaches lunar age two, just sixteen days after birth.
The Hong Kong Observatory’s 1995 conversion table places Lunar New Year on January 31. Its 2026 table places it on February 17. These dates are checks for the calculation.
Dates are converted with lunar-typescript. For dates far in the future, consult the Observatory’s conversion tables and calendar notes; a new moon near midnight can make a predicted calendar date uncertain.
Common questions
What is my lunar age today?
Enter your birth date and leave the reference date set to today. The calculator finds each date’s lunar year, subtracts the birth year and adds one.
Does a leap month add another year?
No. A leap month is part of the same lunar year. Your nominal age increases when the next lunar year starts.
Can I calculate a child’s or an older adult’s age?
Yes. There is no 18–45 age restriction here. Both dates must be within 1901–2099, and the reference date must be on or after the birth date.
How do I find the mother’s lunar age at conception?
Enter the mother’s birth date first and the conception date second. For the traditional chart’s lunar-month lookup, use the Chinese gender calendar, which covers lunar ages 18–45. That folk chart cannot determine a baby’s sex.
Do you store my birth date?
The calculator runs in your browser. It does not submit either date to a server or include dates in analytics events.