This service is calculated based on South Korea’s domestic laws, tax codes, administrative regulations, and cultural systems (such as official age reckoning, military service periods, 4 major social insurances, and traditional lunar calendars). It is fully accessible in English for foreign residents, travelers, and international users in Korea.
Solar to Lunar Calendar & 60 Gapja Converter Guide
This lunar calendar converter uses the official ephemeris data from the Korea Astronomy and Space Science Institute (KASI) to perform precise bidirectional conversion between Gregorian (solar) and Korean lunar dates from 1900 to 2050. Essential for tracking lunar birthdays (especially for elderly family members), ancestor memorial services (Jesa/기제사), and traditional holidays like Seollal (Lunar New Year, lunar 1/1), Chuseok (Harvest Festival, lunar 8/15), and Buddha's Birthday (lunar 4/8). It also computes the traditional 60-Sexagenary cycle (Gapja) used in East Asian astrology and calendar reckoning—year pillar (세차), month pillar (월건), and day pillar (일진)—alongside leap month detection and the 24 solar terms (Ipchun, Gyeongchip, etc.). Because a lunar year is 354 days versus the solar 365, an intercalary leap month is inserted roughly every three years to keep seasonal alignment. This is why a lunar birthday lands on a different solar date each year. Useful for foreign residents attending Korean family events or scholars studying East Asian calendar traditions.
Accurate date conversion between 1900 and 2050 with leap month detection.
Calculates the year, month, and day pillars (Ganji) based on traditional astrology.
Identifies solar dates for Seollal, Chuseok, and Buddha Birthday.
Legal Basis & Official Data Sources
This tool is grounded in the latest laws, regulations, and data from the following official authorities.
Frequently Asked Questions (FAQ)
A lunar year is about 354 days versus 365 for the solar year. To synchronize the lunar calendar with the seasonal solar cycle, an intercalary (leap) month is inserted every 2-3 years, resulting in 13 months in that year. The Korea Astronomy and Space Science Institute officially calculates and announces leap months.
In-Depth Guide Articles
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More about Lunar Calendar Converter on Fredric18 News
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