Free tool
Best day for a purpose
The ranking here combines two calendrical signals: how the day's branch relates to the lunar month's branch, and how the day fits the viewer's own year. No folk table states outright which day suits which task, so this combination is a convention the site chose and published rather than a table copied from memory. Change the viewer and the ranking changes.
Pick a purpose (a wedding, a store opening, signing a contract...) and a date range, and this tool ranks which days in that range best suit your zodiac and Five Elements.
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How this tool ranks good days for a specific purpose
Unlike auspicious hours (which apply generally to any activity in a day), "best day for a purpose" comes from the folk belief that each major life event (a wedding, a business opening, travel, breaking ground, signing a contract) has its own set of day-selection criteria, combining: (1) whether the day falls on a fixed inauspicious date in the lunar month (Tam Nương, Nguyệt Kỵ, Sát Chủ...), (2) whether the day's Five-Element affinity (Metal/Wood/Water/Fire/Earth, from its Heavenly Stem) generates or clashes with the viewer's own elemental destiny (Nạp Âm), and (3) the relationship between the day's Earthly Branch and the viewer's birth-year Branch (Three Harmony/Four Clash/Six Harm), the same age-compatibility groupings used in zodiac matching and auspicious hours.
The tool scores every day in your chosen range against a combination of these criteria (weighted differently depending on the purpose; weddings, for instance, weigh avoiding Nguyệt Kỵ/Tam Nương more heavily than a store opening does), then ranks them from "excellent" to "avoid" so you can compare a whole range of days at once instead of looking each one up individually in a traditional almanac.
This is a synthesis of folk rules recorded in day-selection almanacs passed down over generations, not a scientifically tested calculation. The results are cultural reference, useful for narrowing a wide date range down to a few candidates to weigh alongside practical factors like your work schedule, the weather, and guests' convenience.
Tam Nương ("three ladies") refers to 6 fixed lunar dates each month (3rd, 7th, 13th, 18th, 22nd, 27th) traditionally considered unfavorable for starting major undertakings, said to originate from a legend about three women whose actions on these dates brought misfortune. Nguyệt Kỵ ("month taboo") covers 3 other fixed lunar dates (5th, 14th, 23rd) avoided for similar reasons; between them, roughly a third of any lunar month falls on one of these traditionally inauspicious dates, which is why day-selection almanacs exist in the first place, to help sort through them systematically rather than by memory.
The maximum 62-day range on this tool balances usefulness against reliability: a date far enough in the future can still be scored today (the underlying lunar/Can-Chi calculations don't depend on unpredictable data), but very long ranges make the ranked list unwieldy to compare and encourage picking a date too far ahead to plan around confidently. For longer-term planning, narrow your search to a specific month or two once you have a rough target window in mind.
| Type of event | Commonly prioritized criteria |
|---|---|
| Wedding | Avoid Nguyệt Kỵ, Tam Nương; match Five Elements and Branch compatibility of both people |
| Business opening | An auspicious day, matching the owner's elemental destiny, avoiding Sát Chủ |
| Travel | An auspicious hour/day, a travel direction matching one's Branch |
| Breaking ground, building | Avoid Tam Nương, match the owner's Branch, avoid clashing with Thái Tuế |
| Signing a contract | An auspicious day, matching one's elemental destiny (Nạp Âm) |
Frequently asked questions
How is this different from checking auspicious hours?
Auspicious hours apply generally to any activity within a day. This tool weighs a separate set of criteria for EACH specific type of event (a wedding differs from a store opening), and scores a whole date range at once for comparison.
Why is the lookup range capped at 62 days?
So the ranked results stay easy to compare; a range that's too long makes the list unwieldy and encourages picking a date too far ahead to plan around confidently. For longer-term needs, narrow the search to the specific month or two you're actually considering.
What are Tam Nương and Nguyệt Kỵ?
These are fixed lunar dates each month (Tam Nương: 3rd, 7th, 13th, 18th, 22nd, 27th; Nguyệt Kỵ: 5th, 14th, 23rd) traditionally considered unfavorable for starting a major undertaking.
Does an "excellent" result guarantee things will go smoothly?
No. This is a synthesis of folk rules meant as cultural reference, not a scientifically tested calculation or a guaranteed course of action.
Does the tool need my birth date?
Yes, because results cross-reference your Five-Element destiny and birth-year Branch against each day in the chosen range, so your birth date is needed to calculate your personal elemental destiny correctly.
Can I use this to pick a day for two people (e.g. a wedding)?
Yes, for weddings the tool can cross-reference both the bride's and groom's Five Elements and birth-year Branch to suggest days that work for both.
Why can the same day be good for one purpose but bad for another?
Because each type of event weighs criteria differently (a wedding prioritizes avoiding Nguyệt Kỵ more heavily, a business opening prioritizes an auspicious day more), so the same day's score and rank shifts depending on which purpose you select.