Lunar birthday · Free
Your birthday,
on the other calendar.
Many Koreans have two birthdays: the solar date on the ID card and the lunar date the family celebrates. Find yours, and the day it falls on this year.
Why the lunar birthday still matters
Seaweed soup on the morning of the lunar birthday is a habit older than the solar calendar in Korea; many grandparents never switched.
Because the lunar date moves against the solar one, the same birthday lands on a different day every year — that is what this page tracks.
How to use it
- Pick “I know my solar birthday” or “I only know the lunar one”.
- For a solar date, type it into “Date of birth (solar)”. For a lunar one, choose the year, month and day, and tick “It was a leap month (윤달)” only if it was.
- Press “Convert” to see your lunar birthday, or your solar birth date.
- From a solar date, open “Years ahead” to see which solar day your lunar birthday falls on in the coming years.
If something goes wrong
- If a lunar date is refused, check that the year really had that leap month and that the month has a 30th day.
- Only dates from 1900 to 2050 convert. A Chinese converter can differ by a day; this page follows the Korean lunar calendar.
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Last updated ·
A calendar conversion, the same for everybody, on the Korean lunar calendar as published by the Korea Astronomy and Space Science Institute. The Chinese lunar calendar starts some months on a different day, so a Chinese converter can disagree by a day; this page follows Korea's. Range 1900–2050, the extent of the Korean table.
Quick questions
Why does my lunar birthday fall on a different date every year?
The lunar calendar follows the moon, so its year drifts against the solar one. The same lunar birthday lands on a different solar day each year — this page shows where it falls this year.
Why does a Chinese lunar converter give a different day?
Korea and China publish their own lunar calendars, and some months start on different days. This page follows the Korean calendar published by the Korea Astronomy and Space Science Institute, so it can differ from a Chinese converter by a day. It covers 1900 to 2050.
What if I was born in a leap month?
The leap month (윤달) is kept where it exists. In a year that has no such leap month, the ordinary month with the same number is used — which is also what Korean families do.