Lunar-Solar Calendar Converter
Convert between the solar and Korean lunar calendars, and check the traditional gapja (干支) notation.
Today is 2026-6-12 on the lunar calendar.
Fill in your details on the left and press Calculate to see your result here.
Lunar-Solar Calendar Converter FAQ
What is a leap month, and how do I enter one?
The lunar calendar year is shorter than the solar year, so every few years a month repeats as a 'leap month' (윤달) to stay in sync with the seasons. If the lunar date you're entering falls in a leap month, check the 'This is a leap month' box. Checking it for a month that has no leap month will produce an error.
What date range does this converter support?
This converter handles solar and lunar dates from 1900 to 2050, based on the conversion tables published by Korea Astronomy and Space Science Institute (KASI).
What is gapja (干支)?
Gapja is the traditional sexagenary notation that combines the 10 heavenly stems and 12 earthly branches to label years, months, and days — for example '갑자년' (Gapja year). It's commonly referenced in Korean fortune-telling (saju), naming, and traditional ceremonies.
Can I use this to convert a lunar birthday or memorial date to the solar calendar?
Yes. Enter the lunar date you remember (e.g. a birthday or ancestral memorial date) in 'Lunar → Solar' mode to get the corresponding solar date for that year. Note that a lunar birthday falls on a different solar date each year, so you'll need to recalculate for each year.
This converter follows the lunar-solar conversion standard published by Korea Astronomy and Space Science Institute (KASI) and supports dates from 1900 to 2050 only. Some dates may differ from the lunar calendar systems used in other countries such as China.