How to Pick a Good Day to Marry, Move, or Launch

Choosing an auspicious date — 择日, zé rì — is one of the oldest practical uses of BaZi. Weddings, moving house, opening a shop, signing a contract, a first day at a new job: the idea is to start on a day that does not fight your chart.

It is worth being clear about what this is and is not. A well-chosen day removes friction; it does not guarantee an outcome. Treat it as one input among many, roughly on the level of "don't schedule the launch for the same week as the office move".

What a "good day" is actually checked against

A date is not good or bad on its own. It is good or bad relative to a specific person's chart. The checks are:

1. Does the day clash with your pillars?

Every day has an Earthly Branch. If that branch directly clashes (冲) with one of your four natal branches — especially your day branch or year branch — the day is read as unsettled for you. A clash with the day branch is the one most date-selection traditions avoid outright for anything important.

The clashes are fixed pairs: Rat–Horse, Ox–Goat, Tiger–Monkey, Rabbit–Rooster, Dragon–Dog, Snake–Pig.

2. Does it support or drain your useful element?

Your chart has a useful god (用神) — the element it most needs. A day whose stem and branch carry that element tends to read as supportive. A day heavy in the element your chart already has too much of reads as draining, even if nothing dramatic clashes.

This is why two people looking at the same week get different "best days".

3. The day's officer (十二建除)

Traditional almanacs assign each day one of twelve officers — 建 (Establish), 除 (Remove), 满 (Full), 平 (Balance), 定 (Stable), 执 (Hold), 破 (Break), 危 (Danger), 成 (Complete), 收 (Receive), 开 (Open), 闭 (Close). Some suit certain activities: 成 (Complete) and 开 (Open) for starting things, 定 (Stable) for agreements and moving in, 除 (Remove) for clearing out. 破 (Break) and 闭 (Close) are generally skipped for anything you want to last.

4. The month and year context

A day sits inside a month and a year, each with its own pillar. A day that looks fine in isolation can be pulled down if the month is already clashing your chart, or lifted if the annual pillar is on your side. For 2026 specifically, our Fire Horse year guide covers which signs the year favours and which it strains.

5. Hours, for anything time-specific

If the event has a specific moment — vows, a signing, a ribbon-cutting — the double-hour (时辰) it falls in gets the same clash and support checks as the day. Picking a favourable hour inside an already-favourable day is the finishing touch.

Doing it without a specialist

The five checks above are mechanical. You can run them by hand with an almanac and your chart, or use the Choose Date tab in the app: pick a range and a purpose, and it scores every day against your active chart — best days to pick, worst to avoid, a one-line reason for each, plus a calendar (.ics) export. It also ranks the twelve hours of today.

A short checklist

• Know your Day Master and, ideally, your useful element (how to find them).
• Rule out any day that clashes your day or year branch.
• Prefer days carrying your useful element and a constructive officer (成, 开, 定).
• Check the month and year are not already working against you.
• For a timed event, pick a good hour inside the good day.
• Then stop optimising. Past a point, a slightly better date is not worth rearranging real-life logistics for.