Lunar date, day pillar, solar term & traditional day officers — for any date
China keeps two calendars at once: the Gregorian solar calendar and the lunisolar calendar. The sexagenary cycle then marks year, month, day and hour with 60 repeating pairs of stems and branches.
Each solar term begins when the sun reaches a multiple of 15° of ecliptic longitude. They are the skeleton of the calendar: sexagenary months and years begin at a “section” such as Start of Spring, not at the first of the Gregorian month.
Establish, Remove, Full, Balance, Settle, Hold, Break, Danger, Success, Receive, Open and Close rotate as officers of the day — one of the core traditional frameworks for choosing a date.
The branches clash in six pairs: 子–午, 丑–未, 寅–申, 卯–酉, 辰–戌, 巳–亥. The zodiac animal opposite the day branch is the “day clash”, with a traditional direction to avoid.
The day stem maps to one of the five elements. It shares a name with a person's Day Master in BaZi, but here it simply describes the element of the day itself.
Lunar conversion, pillars and solar terms are computed in your browser for 1900–2100. The dates you look up are never uploaded.
Traditional almanac notes are derived from systems such as the Twelve Day Officers, the Twenty-Eight Mansions and the shen sha. This page uses the Twelve Day Officers: the officer for a day comes from the relationship between the day branch and the month branch, then maps to conventional lists of suitable and unsuitable activities.
No. An almanac describes a day; a BaZi chart describes a person and needs the birth date, time and place, plus true-solar-time correction. Both use the sexagenary calendar but answer different questions.
Because sexagenary months begin at a “section”. The Tiger month, for example, runs from Start of Spring to Awakening of Insects and can straddle February and March.
No. Everything is computed in your browser and the date you enter is never sent to a server.