What is my cung Mệnh? How a Tử Vi chart places your Destiny palace

Tử Vi in one paragraph, and why the Mệnh palace matters

Tử Vi Đẩu Số is Vietnam's Purple Star astrology: the same system as Chinese Zi Wei Dou Shu — the same 紫微斗數, the same twelve palaces, the same stars — read under Vietnamese names. A chart, the lá số Tử Vi, arranges your birth into twelve cung (palaces): Mệnh, Huynh Đệ, Phu Thê, Tử Tức, Tài Bạch, Tật Ách, Thiên Di, Nô Bộc, Quan Lộc, Điền Trạch, Phúc Đức and Phụ Mẫu, and places the stars across them, led by Tử Vi, the Purple Star itself.

Everything in the chart hangs off one palace: the cung Mệnh, the Destiny or Life palace. It is placed first, before any star; the Five-Element bureau (cục) that times the whole chart is derived from it; and the stars that land inside it are read as the grain of your character. Ask a Tử Vi reader one question about a stranger's chart and "where is the Mệnh, and what sits in it?" is that question.

The placement is pure arithmetic — a counting rule on a twelve-spoke wheel. That is what this post walks through, with the exact method the AsterNym Tử Vi calculator runs.

What you need first: the lunar month and the birth hour

Tử Vi does not read your Gregorian birthday directly. The chart is cast from your birth date on the âm lịch, the Vietnamese lunar calendar — and Vietnamese practice means the Vietnamese calendar, not the Chinese one. Vietnam has computed its calendar on UTC+7 since 1968 while China uses UTC+8, so when a new moon falls inside that one-hour window the lunar month begins a day earlier in Vietnam, and the two calendars can even place a leap month differently. Most dates convert identically; the edge cases are real.

The second ingredient is your birth hour, and Tử Vi needs it more than almost any other system. Hours are counted in the twelve traditional double-hours, each named for an Earthly Branch:

Only the giờ Tý straddles midnight — 23:00 to 00:59 — which is why a birth between 23:00 and 23:59 keeps giờ Tý as its hour but is charted on the next day's lunar date. Schools differ on that handling; our calculator follows the roll-forward convention, and it is why calculators ask for the clock time rather than the watch name. Every other watch is a clean two-hour block starting on an odd clock hour.

A rough birth time is a real problem here: move one watch and the Mệnh moves one palace, and every star reading moves with it. If you only know "morning", the chart cannot be cast reliably — our piece on reading a chart without a birth time covers what can and cannot be salvaged.

Placing the cung Mệnh: forward the months, back the hours

The twelve palaces sit on the twelve Earthly Branches, arranged in a fixed wheel: Tý, Sửu, Dần, Mão, Thìn, Tỵ, Ngọ, Mùi, Thân, Dậu, Tuất, Hợi. The counting rule takes three steps:

The branch you finish on holds your cung Mệnh. Three worked examples, straight from the calculator's own arithmetic:

— Lunar month 1, giờ Tý: start Dần, forward zero, back zero — the Mệnh sits in Dần.

— Lunar month 8, giờ Tý: forward seven branches to Dậu, back zero — the Mệnh sits in Dậu.

— Lunar month 5, giờ Mão: forward four branches to Ngọ, back three — the Mệnh sits in Mão.

The same count run the other way places the cung Thân, the Body palace: forward the months as before, then forward the hours instead of back. A birth in month 5, giờ Mão puts the Thân in Dậu, opposite its Mệnh in Mão. And because stepping back by giờ Tý or Ngọ is the same as stepping forward by it on a twelve-spoke wheel, anyone born in those two watches has Mệnh and Thân sharing one palace.

You can run this on paper in under a minute — the slips happen in the calendar conversion, not the counting. The AsterNym calculator converts your date on the Vietnamese calendar and places both palaces for you.

From the Mệnh to the full lá số

The Mệnh palace is the anchor, and the rest of the chart is derived in a strict order. First the other eleven palaces fill in around the wheel from the Mệnh. Then each palace receives a Heavenly Stem by the "Five Tigers" rule (ngũ hổ độn), which fixes the stem of the Dần palace from your birth-year stem and runs the rest forward.

The stem and branch of the Mệnh palace together determine your cục, the Five-Element bureau, through the nạp âm correspondences — Thủy nhị cục (Water 2), Mộc tam cục (Wood 3), Kim tứ cục (Metal 4), Thổ ngũ cục (Earth 5) or Hỏa lục cục (Fire 6). The cục is not read off your birth year; it only exists once the Mệnh has been placed, which is why the Mệnh comes first.

Finally the cục number and your lunar day place Tử Vi, the Purple Star, and the other thirteen major stars chain off its position: Thiên Cơ, Thái Dương, Vũ Khúc, Thiên Đồng, Liêm Trinh, Thiên Phủ, Thái Âm, Tham Lang, Cự Môn, Thiên Tướng, Thiên Lương, Thất Sát and Phá Quân. Whichever of them land in your Mệnh palace are the headline of the reading.

What the cung Mệnh is read for

Tradition reads the Mệnh as the core of character and life direction: the temperament you lead with, the way fortune tends to arrive for you, the lens the other eleven palaces are read through. A Mệnh holding Tử Vi itself is read very differently from one holding Thất Sát or an "empty" Mệnh borrowing its stars from the opposite palace — the combinations are where practitioners spend their decades.

The Thân palace is read as the second half of the answer: where the Mệnh describes what you are, the Thân is read as what you grow into after mid-life. The pairing — which palace the Thân shares, since it always coincides with one of six palaces — is itself read as a signature.

Held loosely, the Mệnh works the way a key signature works in music: it does not dictate the melody of a life, but practitioners read everything else in its key.

What it is not is a prediction engine. Nothing in the counting knows your future; the chart is a traditional lens, internally rigorous, and internal rigour is not the same thing as being shown to work. That is the same honest footing we give every system on this site — our survey of Chinese divination systems draws that map.

Tử Vi or Zi Wei — does the name change the chart?

No. Tử Vi Đẩu Số and Zi Wei Dou Shu are one system under two names: Tử Vi, Thiên Cơ and Thái Dương are the Sino-Vietnamese readings of the very characters a Chinese chart writes as 紫微, 天機 and 太陽. A practitioner reading either script is looking at the same star, and AsterNym computes both presentations on one engine.

The one place the traditions genuinely part is the calendar underneath, as above: Vietnamese almanacs compute the lunar months on Vietnam's clock. For most birth dates the charts agree exactly; for a birth near a new moon that falls between 23:00 and 23:59 Vietnam time, the Vietnamese chart can sit a month-day apart from the Chinese one. If your family kept your âm lịch birthday, that is the date to trust.

If you want the system read against its Chinese cousins — how Tử Vi divides the work with BaZi, which reads the same birth through four pillars instead of twelve palaces — the divination survey linked above puts them side by side.

What is the cung Mệnh in Tử Vi?

The cung Mệnh is the Destiny or Life palace of a Tử Vi chart, the most important of the twelve cung. It is placed from the lunar birth month and the birth hour, it determines the chart's Five-Element bureau (cục), and the stars that fall in it are read as the core of a person's character.

How do I find my cung Mệnh?

Convert your birth date to the Vietnamese lunar calendar, then count on the wheel of twelve branches: start at Dần, count forward one branch per lunar month beginning with month 1 on Dần, then count backward one branch per double-hour beginning with the hour of Tý as zero. The branch you land on holds your cung Mệnh. Born in lunar month 8 in the hour of Tý, for example, your Mệnh sits in Dậu.

Do I need my exact birth time for Tử Vi?

You need at least the two-hour window. The hour count moves the Mệnh one palace per double-hour, so a birth time that is wrong by one watch moves the Destiny palace and re-reads the whole chart. Without any birth time, a lá số Tử Vi cannot be cast reliably.

What is the cung Thân, and can it share a palace with the Mệnh?

The cung Thân is the Body palace, read as the person you grow into after mid-life. It is placed by the same count as the Mệnh but stepping forward by the hour instead of backward. Anyone born in the hour of Tý or the hour of Ngọ has the two counts land together, so their Mệnh and Thân share one palace.

Is Tử Vi the same as Zi Wei Dou Shu?

Yes — one system, two names. Tử Vi Đẩu Số is the Vietnamese reading of the same characters as Chinese Zi Wei Dou Shu: the same twelve palaces, fourteen major stars and placement rules. The practical difference is the calendar: Vietnam computes its lunar calendar on UTC+7, China on UTC+8, so a birth near certain new moons can convert to different lunar dates in the two traditions.