Auspicious Date Checker

The Chinese almanac, called the Tung Shing (通書) or Huang Li (黃曆), is a calendar that annotates each day with several independent cycles. It has been printed and consulted continuously for well over a thousand years, and for much of that history it was among the most widely owned books in Chinese households. Its function was practical: it told you when to plant, when to travel, when to hold a ceremony, and when convention advised waiting.

The layers this tool reads are the ones with clearly documented formulas:

• The day pillar (日柱). Every day carries one of sixty stem and branch pairs, cycling continuously without reference to months or years. This tool computes it from the Julian Day Number, the same engine the site's Bazi calculator uses.
• The Twelve Day Officers (建除十二神). Each day receives one of twelve officers, found from the relationship between the day branch and the solar-term month branch. Each officer carries traditional lists of suitable and unsuitable activities.
• The Golden and Black Road day gods (黃道黑道). Twelve deities cycle through the days, six on the golden road and six on the black, adding a second opinion to the officer.
• Nayin (納音). Each pair of days in the sixty cycle shares one of thirty poetic element images, such as Fire in the Furnace or Gold in the Sea.
• The six clash (六沖). Each day branch opposes one zodiac branch across the cycle, which is the origin of the familiar advice that a day may clash with a particular animal sign.

A full printed Tung Shing layers many further deities and taboos that this tool does not compute. Where the layers disagree, traditional practice weighs them rather than tallying them, which is why an almanac was read with a practitioner or with experience rather than as a scoreboard.

The Day Officer formula depends on which solar-term month the date falls in, so the month boundary matters. In the Zi Ping (子平) tradition that this site follows throughout, the astrological year turns at Li Chun (立春), the solar term near 4 February, and each month turns at its own solar term rather than at a new moon.

Chinese New Year is a lunar festival calculated differently and can fall as much as several weeks from Li Chun. Using it as the boundary would give a different month branch for dates in that window, and therefore a different officer. The site uses Li Chun and solar terms consistently across the calculator, the almanac, and this checker so that results agree with each other. If you want the background, we explain the solar term year boundary in Bazi and where it parts ways with the festival calendar.

It does not predict outcomes. It reports convention: what the tradition has historically associated with a day of this shape, for a purpose of this kind. Whether that association means anything to you is yours to decide.

It also does not account for your own chart. Traditional date selection at its most careful compares a candidate date against the birth chart of the people involved, which is beyond what a single date and purpose can capture. If you want to bring your own chart into it, the date finder includes a zodiac clash check, and the Bazi calculator will give you the chart itself.