Lunar Age Calculator
Enter your birthday to compare your chronological age with a simplified traditional age estimate, and see your zodiac and Chinese zodiac.
What Is Lunar Age?
"Lunar age" typically refers to traditional age reckoning systems used in East Asian cultures (like China, Korea, and Vietnam). Unlike the international system where you start at 0 and age up on your birthday, traditional systems often consider a child to be 1 year old at birth and add a year at the Lunar New Year.
Learn more on Wikipedia: East Asian age reckoning
Lunar Age vs Chronological Age
The key differences are the starting point and the date of aging up:
- Chronological Age: Starts at 0. Increases on your actual birthday.
- Lunar/Traditional Age: Often starts at 1 (accounting for time in the womb). Increases on the New Year (Lunar or Solar depending on the specific tradition).
This means your "Lunar Age" is usually 1 or 2 years greater than your international age.
Lunar Age Calculation Examples
Example 1
Birth date: 2000-07-10, assume today is 2026-02-01.
Chronological Age: 25 (birthday hasn’t happened yet this year).
Traditional Age: 2026 - 2000 + 1 = 27 (often 1–2 years higher).
Example 2
Birth date: 2025-12-31, assume today is 2026-01-01.
Chronological Age: 0.
Traditional Age: counted as 1 at birth, then +1 at the New Year, so it can show as 2.
FAQ
What is the difference between lunar age and actual age?
Actual (chronological) age is calculated from your birth date to today. Lunar age (or traditional East Asian age) often starts at 1 year old at birth and adds a year at the Lunar New Year, making it 1-2 years higher than your actual age.
How is lunar age used in different countries?
Usage varies by region and is often cultural rather than official. For example, in China it can appear in traditional customs (seniority, celebrations, fortune-telling contexts). In Korea, the traditional “Korean age” system was widely used (often aging up together at the Solar New Year), but South Korea adopted the international age system for most legal and administrative purposes in June 2023. Similar traditional ideas exist in places like Vietnam, mainly used in cultural settings.
Is lunar age still commonly used today?
While official systems have shifted to international age, the concept remains culturally relevant in parts of East Asia for determining social hierarchy, horoscopes, and traditional celebrations.