Huangli Date Selection: How the Suitable and Avoid Lines Are Worked Out
There is a line of small print in my phone calendar: suitable for marriage, suitable for opening a business, avoid breaking ground. I used to skim it and swipe past, until I had to fix a date for something that mattered. Then I sat down with it properly for a few days — and on two of those days, calendars from two different sources gave me opposite answers. One said suitable, the other said avoid.
The first thing I learned that day was this: a huangli page is not one number. It is several sets of rules stacked together.
What This Method Looks At
Huangli date selection means picking, within a given span of time, the days and hours that fit the matter at hand. It reads the nature of the time itself, so no birth information is needed; birth details come in only if you want to weigh the date against a particular person.
Where the Suitable and Avoid Lines Come From
The suitable-and-avoid entries on one almanac page are usually the result of several systems stacked together: one is the duty system that rotates with the day count (the Twelve Duty Officers, for instance), another is the rotation of the Twenty-Eight Mansions, and on top of that come judgments from a range of auspicious and inauspicious spirits (shen sha). The same day can yield conclusions in these systems that do not agree with each other; what finally gets printed as two lines, suitable and avoid, is a presentation that follows selection and stacking.
That is also why different almanacs make different selections from the same body of rules, producing the situation in which one source says suitable and another says avoid. It is not a misprint; it is a difference in editorial convention.
The Usual Process of Choosing a Date
- Fix the range: first mark out the span you can choose from — for example, the usable days in a given month.
- Rule out hard conflicts: set aside first the days that clearly clash with the matter at hand.
- Check the duty officer and the mansion: look at the duty officer and the rotating mansion of the remaining days and pick the ones whose nature fits.
- Fix the hour: once the day is settled, look at how that day divides into hours and choose a suitable stretch.
If you want the person taken into account, add the birth information of the party concerned and filter further.
The Authoritative Basis for the Lunisolar Calendar and Solar Terms
The compilation and promulgation of the lunisolar calendar has a national standard behind it, and official institutions publish material for converting between Gregorian and lunisolar dates (see the sources below). For astronomical moments such as solar terms and new moons, official almanacs and astronomical bodies are a steadier reference than the various perpetual-calendar aggregator pages.
Its Limits
One thing to be clear about from the start: the suitable-and-avoid entries of a huangli are the product of a traditional date-selection system. They belong to folk culture, and they are not a basis for judging how something will turn out. Second, almanacs differ in convention, so when you are choosing a date it is best to use one almanac from beginning to end, rather than switching sources midway and contradicting yourself. Finally, for real arrangements such as a wedding, a journey or a business opening, custom is only one side of the question — the practical conditions matter too. What the almanac gives you is a reference, not a decision.
FAQ
Q: How are leap months calculated? The arrangement of leap months is decided by the calendar system and belongs to the official almanac. You do not need to work it out yourself; consulting the official conversion table is the safer route.
Q: If it is past 11 p.m., which day does that count as? The Zi hour straddles the day change, and conventions differ: some count it as the Zi hour of the current day, others as the next day. Settle this before you start, and do not change convention halfway through.
Q: Two almanacs disagree — which one should I trust? Look first at the convention each one relies on. If you cannot tell, pick one authoritative source and stay with it; that is more useful than comparing several back and forth.
Q: Must a wedding be set on an auspicious day? That is a choice at the level of custom. In practice, what matters more is the timing of both parties and the family arrangements. If a disagreement arises over the date, sitting down and laying out the practical conditions usually works better than arguing about the day.
Where to Start
If you need to pick a time range for a specific matter, you can go through the flow on this site: describe the matter and roughly when it should happen, and the system will suggest a method, or you can specify Huangli date selection. You will then see the suitable-and-avoid comparison for those days with an explanation, and can export it to keep if you need to. In the Zhanbu Mizhi flow, the calendar data comes from regulated sources rather than manual annotation.
Disclaimer: This article covers traditional culture and folk custom. It is for entertainment and self-reflection only, and does not constitute medical, psychological, investment, legal or marital decision advice. Please do not submit sensitive personal information such as ID numbers or detailed addresses. If you experience persistent insomnia, anxiety or physical discomfort, please consult a doctor or a qualified professional.
Sources
- Compilation and Promulgation of the Lunisolar Calendar, GB/T 33661-2017, National Standards Full-Text Public System: https://openstd.samr.gov.cn/bzgk/gb/newGbInfo?hcno=E107EA4DE9725EDF819F33C60A44B296 (accessed 2026-09-17)
- Gregorian and lunisolar conversion table, Hong Kong Observatory: https://www.hko.gov.hk/tc/gts/time/conversion.htm (accessed 2026-09-17)