The hai hour in bazi is the Pig hour (亥 Hài), 21:00–22:59 — late evening, the last double-hour before midnight, when the household quiets, the fires bank and the water of the day settles into stillness. In element terms 亥 is yang Water: deep, broad, at rest. It is the hour of completion and return, the cycle closing so it can begin again at the Rat.
The Pig hour (亥) and its time range
Hai is the twelfth and final Earthly Branch. Its Water is the great reservoir into which the year and the day drain — full, calm, generous. This is the hour of contentment and inward peace, of letting go of the day’s striving. There is an easy, well-fed abundance in the Pig hour, and a philosophical, unbothered depth.
The Pig hour pillar by day stem
The stem on 亥 follows from the day stem through the Five Rats rule (五鼠遁 wǔshǔdùn):
| Day stem | Pig hour pillar |
|---|---|
| 甲 Jiǎ | 乙亥 |
| 乙 Yǐ | 丁亥 |
| 丙 Bǐng | 己亥 |
| 丁 Dīng | 辛亥 |
| 戊 Wù | 癸亥 |
| 己 Jǐ | 乙亥 |
| 庚 Gēng | 丁亥 |
| 辛 Xīn | 己亥 |
| 壬 Rén | 辛亥 |
| 癸 Guǐ | 癸亥 |
The seat and what sits beneath it
Two layers make this pillar worth reading closely. The first is the stem the table just gave you: the hour pillar is a ten-god seat, and the stem’s Ten God (十神 shíshén) against your Day Master names what occupies the children and later-life palace. A Ding 丁 day born in this hour carries 辛亥, and 辛 is Indirect Wealth (偏财 piāncái) for Ding — opportunity and enterprise at the destination. A Wu 戊 day carries 癸亥 instead, where 癸 is Direct Wealth (正财 zhèngcái). Same evening, different endings; the whole grid sits on the master hour stem table.
The second layer is inside the branch. The hidden stems (藏干 cánggān) of Hai are Rén 壬 (Yang Water) as the main qi and Jiǎ 甲 (Yang Wood). The 壬 is the reservoir itself — a strong root for any Water in the chart. The 甲 is the seed of Wood floating in that Water: growth already beginning inside the hour of rest, which is why Hai is also counted among the “growth” branches that open new cycles. For that same Ding day, the hidden 壬 is Direct Officer (正官 zhèngguān) and the hidden 甲 is Direct Resource (正印 zhèngyìn) — discipline and support tucked beneath the Wealth on the surface. Compare all twelve branches on the hidden stems table.
What being born in the Pig hour colours
The hour is the destination pillar — children, output, ambition and later life. Deep, still Water at that destination reads as generosity and inner ease: people whose later chapters tend toward abundance, warmth and a settled, unhurried wisdom, and who are content to give without keeping score. The Pig hour carries sincerity and a wide, tolerant heart. Its risk is indulgence or passivity — Water that pools rather than moves. Whether that depth reads as contentment or as complacency is decided, as always, by the balance of the whole chart.
Clock time, solar time and the Pig boundary
The window given for the Pig hour, 21:00–22:59, is true solar time — pinned to the sun’s actual position rather than the number printed on a birth certificate. Two corrections can carry a birth across the edge of this hour. The first is longitude: a birth city rarely sits exactly on the meridian its time zone is set to, and in Singapore, where clocks run on UTC+8 while the island lies nearer 104°E, civil time can lead solar time by close to half an hour. The second is the equation of time, a seasonal wobble of up to about a quarter-hour in either direction.
Near either edge of the Pig hour those minutes are not cosmetic. They can move a chart into the hour before or after — and the later edge matters doubly here, since 23:00 opens the contested late-Zi window. A birth logged at 22:55 that is really 23:10 in solar terms has crossed out of the Pig hour entirely. This is the quiet adjustment that separates a rough chart from an accurate one, so if your recorded time sits within twenty minutes of 21:00 or 23:00, treat the neighbouring hour as a live possibility until the solar correction is done; the calculator linked below makes both corrections automatically.
Pig hour questions, answered
How do I find my Pig hour pillar by hand?
Take the day stem — the upper character of your day pillar, the same character as your Day Master — confirm the solar-corrected birth time falls within 21:00–22:59, then read your row in the table above. The result is the complete hour pillar; the stem’s Ten God and the two hidden stems of 亥 are what a reader then interprets.
What happens if the birth crossed into 23:00?
Then the chart has left the Pig hour for the Rat hour, and between 23:00 and 23:59 the late-Zi (晚子時 wǎn zǐshí) question arises. This site’s standing convention: the hour pillar takes the next day’s stem while the day pillar stays with the calendar day of birth. Schools genuinely differ on this, and the reasoning is set out on the birth hour and hour pillar page.
What if the birth time is not known at all?
Read the chart on its six known characters — year, month and day still fix the season, the Day Master and the spouse palace — and hold children and later-life conclusions loosely. An evening birth remembered as “after dinner, before the news” narrows the field to two or three candidate hours; each candidate pillar can then be tested against known life events until one clearly fits. Avoid inventing a time just to complete the grid.
Fixing your own Pig hour
The hour pillar is derived, not read off a calendar. To see 亥 among all sixty hour pillars, use the master hour stem table; the evening approaches through the Dog hour page, and the cycle then closes and reopens at the Rat hour page, whose late-Zi (晚子時 wǎn zǐshí) split begins one minute after the Pig hour ends. For the general logic of hour boundaries, see the birth hour and hour pillar page. Or plot your chart free with the calculator and read your hour pillar to the minute.