{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"lunar-calendar-converter"},"result":{"entity_type":"calculator","id":"lunar-calendar-converter","calculator_id":"lunar-calendar-converter","canonical_url":"https://tttkmbb.com/lunar/lunar-calendar-converter","name":"Lunar Calendar Converter (农历)","title":"Lunar Calendar Converter – Gregorian Date to Chinese Lunar Date, Ganzhi, Zodiac and Solar Term","category":"lunar","category_name":"Chinese Calendar","tool_name":"convert_solar_to_lunar","featured_mcp_tool":true,"description":"Converts a Gregorian date to the Chinese lunisolar calendar (农历 nongli): lunar year, month (with leap-month flag), day, the sexagenary stems and branches (干支 ganzhi) of year, month and day, zodiac animal, nayin (纳音), the current 24-solar-term period and any traditional festival on that day.","use_when":"You need the Chinese lunar date, ganzhi day/month/year, zodiac year or current solar term for a given Gregorian date (defaults to today).","do_not_use_when":"You start from a lunar date and need the Gregorian date (use lunar-to-solar), need a person's zodiac with the 立春 boundary option (use chinese-zodiac), or need the astronomical moon phase (use moon-phase).","inputs":[{"name":"date","label":"Gregorian date","type":"date","required":false,"default":"today","description":"Civil date in China Standard Time (UTC+8), 1900–2100; defaults to the current UTC date.","example":"2026-09-24"}],"outputs":[{"name":"lunar_year","label":"Lunar year","type":"integer","decimals":0,"description":"Lunar year number (the year that began at the preceding Chinese New Year)."},{"name":"lunar_month","label":"Lunar month","type":"integer","decimals":0,"description":"Lunar month number 1–12."},{"name":"is_leap_month","label":"Leap month","type":"boolean","decimals":4,"description":"true when the date falls in an intercalary month (闰月 runyue)."},{"name":"lunar_day","label":"Lunar day","type":"integer","decimals":0,"description":"Day of the lunar month, 1–30."},{"name":"lunar_date_chinese","label":"Lunar date (Chinese)","type":"string","decimals":4,"description":"Written form, e.g. 二〇二六年八月十四."},{"name":"lunar_date_text","label":"Lunar date (English)","type":"string","decimals":4,"description":"Readable form, e.g. 8th lunar month, day 14 (八月十四)."},{"name":"month_name","label":"Month name","type":"string","decimals":4,"description":"Traditional month name (正月 … 腊月, prefixed 闰 for a leap month)."},{"name":"day_name","label":"Day name","type":"string","decimals":4,"description":"Traditional day name (初一 … 三十)."},{"name":"month_days","label":"Days in lunar month","type":"integer","decimals":0,"description":"Length of this lunar month (29 or 30)."},{"name":"leap_month_this_year","label":"Leap month of the year","type":"integer","decimals":0,"description":"Number of the leap month in this lunar year, 0 when the year has none."},{"name":"year_ganzhi","label":"Year ganzhi (干支)","type":"string","decimals":4,"description":"Sexagenary year of the lunar year, e.g. 丙午."},{"name":"year_ganzhi_pinyin","label":"Year ganzhi (pinyin)","type":"string","decimals":4,"description":"Pinyin of the year ganzhi, e.g. Bingwu."},{"name":"year_english","label":"Year (element + animal)","type":"string","decimals":4,"description":"Stem element and zodiac animal, e.g. Fire Horse."},{"name":"zodiac","label":"Zodiac (生肖)","type":"string","decimals":4,"description":"Zodiac animal of the lunar year with its character, e.g. Horse (马)."},{"name":"nayin_year","label":"Nayin (纳音) of the year","type":"string","decimals":4,"description":"Nayin melodic element of the year ganzhi, e.g. 天河水 · Milky-way Water."},{"name":"month_ganzhi","label":"Month ganzhi","type":"string","decimals":4,"description":"Sexagenary month by solar-term months (节气月): 寅 month starts at 立春, stems by the 五虎遁 rule."},{"name":"month_ganzhi_pinyin","label":"Month ganzhi (pinyin)","type":"string","decimals":4,"description":"Pinyin of the month ganzhi."},{"name":"day_ganzhi","label":"Day ganzhi","type":"string","decimals":4,"description":"Sexagenary day (continuous 60-day cycle; 1949-10-01 = 甲子)."},{"name":"day_ganzhi_pinyin","label":"Day ganzhi (pinyin)","type":"string","decimals":4,"description":"Pinyin of the day ganzhi."},{"name":"weekday","label":"Weekday","type":"string","decimals":4,"description":"Day of the week."},{"name":"current_solar_term","label":"Current solar term (节气)","type":"string","decimals":4,"description":"Solar-term period the date falls in and the date it began."},{"name":"next_solar_term","label":"Next solar term","type":"string","decimals":4,"description":"Next solar term and its date."},{"name":"days_to_next_term","label":"Days to next term","type":"integer","unit":"days","decimals":0,"description":"Days until the next solar term."},{"name":"is_solar_term_day","label":"Solar-term day","type":"boolean","decimals":4,"description":"true when the date is itself a solar-term day."},{"name":"festival","label":"Festival","type":"string","decimals":4,"description":"Traditional festival(s) on this day (春节, 元宵节, 龙抬头, 上巳节, 端午节, 七夕, 中元节, 中秋节, 重阳节, 寒衣节, 下元节, 腊八节, 小年, 除夕, 清明节, 冬至) or \"none\"."},{"name":"julian_day_number","label":"Julian Day Number","type":"integer","decimals":0,"description":"Julian Day Number of the civil date."}],"input_schema":{"type":"object","properties":{"date":{"description":"Civil date in China Standard Time (UTC+8), 1900–2100; defaults to the current UTC date.","type":"string","format":"date","default":"today","examples":["2026-09-24"]}},"additionalProperties":false},"output_schema":{"type":"object","properties":{"lunar_year":{"description":"Lunar year number (the year that began at the preceding Chinese New Year).","type":"integer"},"lunar_month":{"description":"Lunar month number 1–12.","type":"integer"},"is_leap_month":{"description":"true when the date falls in an intercalary month (闰月 runyue).","type":"boolean"},"lunar_day":{"description":"Day of the lunar month, 1–30.","type":"integer"},"lunar_date_chinese":{"description":"Written form, e.g. 二〇二六年八月十四.","type":"string"},"lunar_date_text":{"description":"Readable form, e.g. 8th lunar month, day 14 (八月十四).","type":"string"},"month_name":{"description":"Traditional month name (正月 … 腊月, prefixed 闰 for a leap month).","type":"string"},"day_name":{"description":"Traditional day name (初一 … 三十).","type":"string"},"month_days":{"description":"Length of this lunar month (29 or 30).","type":"integer"},"leap_month_this_year":{"description":"Number of the leap month in this lunar year, 0 when the year has none.","type":"integer"},"year_ganzhi":{"description":"Sexagenary year of the lunar year, e.g. 丙午.","type":"string"},"year_ganzhi_pinyin":{"description":"Pinyin of the year ganzhi, e.g. Bingwu.","type":"string"},"year_english":{"description":"Stem element and zodiac animal, e.g. Fire Horse.","type":"string"},"zodiac":{"description":"Zodiac animal of the lunar year with its character, e.g. Horse (马).","type":"string"},"nayin_year":{"description":"Nayin melodic element of the year ganzhi, e.g. 天河水 · Milky-way Water.","type":"string"},"month_ganzhi":{"description":"Sexagenary month by solar-term months (节气月): 寅 month starts at 立春, stems by the 五虎遁 rule.","type":"string"},"month_ganzhi_pinyin":{"description":"Pinyin of the month ganzhi.","type":"string"},"day_ganzhi":{"description":"Sexagenary day (continuous 60-day cycle; 1949-10-01 = 甲子).","type":"string"},"day_ganzhi_pinyin":{"description":"Pinyin of the day ganzhi.","type":"string"},"weekday":{"description":"Day of the week.","type":"string"},"current_solar_term":{"description":"Solar-term period the date falls in and the date it began.","type":"string"},"next_solar_term":{"description":"Next solar term and its date.","type":"string"},"days_to_next_term":{"description":"Days until the next solar term. Unit: days.","type":"integer","x-unit":"days"},"is_solar_term_day":{"description":"true when the date is itself a solar-term day.","type":"boolean"},"festival":{"description":"Traditional festival(s) on this day (春节, 元宵节, 龙抬头, 上巳节, 端午节, 七夕, 中元节, 中秋节, 重阳节, 寒衣节, 下元节, 腊八节, 小年, 除夕, 清明节, 冬至) or \"none\".","type":"string"},"julian_day_number":{"description":"Julian Day Number of the civil date.","type":"integer"}}},"formula":"lunar month = interval between successive new moons (instants at 120° E, UTC+8); month 11 contains the winter solstice; a leap month is the first month without a major solar term (中气) in a 13-month solstice-to-solstice suite; year_ganzhi index = (lunar_year − 4) mod 60; day_ganzhi index = (JDN + 49) mod 60; month branch = 寅 from 立春, one branch per odd solar term","method":"Astronomical computation (Meeus VSOP87 solar longitude, Meeus ch. 49 new moons, Espenak–Meeus ΔT) following the GB/T 33661-2017 rules, checked against Hong Kong Observatory tables; pre-1929 dates use Beijing local mean time as the published calendars did. Traditional calendar/cultural reference calculation; not a prediction, medical, legal or financial advice.","sources":[{"name":"Chinese calendar (Wikipedia) – calendar rules as standardised in GB/T 33661-2017","url":"https://en.wikipedia.org/wiki/Chinese_calendar","type":"reference","retrieved_at":"2026-09-24"},{"name":"Hong Kong Observatory – Gregorian-Lunar Calendar Conversion Table","url":"https://www.hko.gov.hk/en/gts/time/conversion.htm","type":"government","retrieved_at":"2026-09-24"},{"name":"Meeus J. (1998) Astronomical Algorithms, 2nd ed., Willmann-Bell (solar longitude, nutation, ΔT, new moons)","url":"https://en.wikipedia.org/wiki/Jean_Meeus","type":"textbook","retrieved_at":"2026-09-24"}],"freshness":{"type":"daily","max_age_seconds":86400,"note":"Depends on the current date."},"examples":[{"name":"2026-09-24 (八月十四, 丙午年)","inputs":{"date":"2026-09-24"},"expected":{"lunar_month":8,"lunar_day":14,"is_leap_month":false,"lunar_date_chinese":"二〇二六年八月十四","year_ganzhi":"丙午","month_ganzhi":"丁酉","day_ganzhi":"辛丑","zodiac":"Horse (马)","current_solar_term":"秋分 (Qiufen, Autumn Equinox) since 2026-09-23","days_to_next_term":14,"festival":"none","julian_day_number":2461308},"url":"https://tttkmbb.com/api/v1/calculate/lunar-calendar-converter?date=2026-09-24"},{"name":"2025-07-25 (闰六月初一)","inputs":{"date":"2025-07-25"},"expected":{"lunar_month":6,"is_leap_month":true,"lunar_day":1,"lunar_date_chinese":"二〇二五年闰六月初一","year_ganzhi":"乙巳","zodiac":"Snake (蛇)","leap_month_this_year":6,"month_days":29},"url":"https://tttkmbb.com/api/v1/calculate/lunar-calendar-converter?date=2025-07-25"}],"faq":[{"q":"Which time zone decides the lunar date?","a":"New moons and solar terms are evaluated in China Standard Time (UTC+8, 120° E) as the official calendar prescribes; the date you enter is taken as a civil date in that zone. Dates before 1929 use Beijing local mean time (UTC+7:45:40), reproducing the calendars published then."},{"q":"Why can the year ganzhi differ between sources?","a":"Almanacs tied to the lunar calendar switch the year at Chinese New Year (used here); Bazi (八字) practice switches it at 立春. Between the two dates the two conventions give different years; a note flags this when it applies."},{"q":"How are month ganzhi assigned?","a":"By solar-term months: the 寅 month begins at 立春 and each following odd term (惊蛰, 清明 …) starts the next branch; the stem follows the 五虎遁 rule from the year stem."}],"tags":["lunar calendar","chinese calendar converter","农历","ganzhi","solar term","chinese zodiac year"],"related":[{"calculator_id":"lunar-to-solar","reason":"Reverse conversion from a lunar date to the Gregorian date."},{"calculator_id":"chinese-zodiac","reason":"Zodiac sign of a birth date with the 立春 boundary option and compatibility tables."},{"calculator_id":"moon-phase","reason":"Astronomical moon phase and illumination for the same date."}],"links":{"html":"https://tttkmbb.com/lunar/lunar-calendar-converter","markdown":"https://tttkmbb.com/lunar/lunar-calendar-converter.md","json":"https://tttkmbb.com/lunar/lunar-calendar-converter.json","api":"https://tttkmbb.com/api/v1/calculate/lunar-calendar-converter","schema":"https://tttkmbb.com/api/v1/calculators/lunar-calendar-converter","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-24"},"timestamp":"2026-09-24T08:34:21Z"}