How Old Are You, Really?
虚岁 · Nominal Age and the Start of Luck
Every BaZi reading bumps into a counting problem that surprises most newcomers: BaZi does not count your age the way your ID card does. The tradition uses 虚岁 (xū suì) — nominal, or "imaginary", age — and it runs on a completely different clock from the birthday year. Understand this small convention and half the confusion in your Da Yun timeline evaporates.
Nominal age: born already one
In nominal-age counting you are one year old on the day you are born, and you gain a year at every Chinese New Year (or, in strict readings, at 立春) rather than on your birthday. The reasoning is cultural: the nine months in the womb count. The practical effect is visible immediately — a baby born on New Year's Eve is two years old the next morning, an old joke every Chinese family knows. When a chart says your first Da Yun chapter "starts at age 3", it means age 3 by this count.
Qi Yun: the launch moment
Chapters of luck do not begin at birth. There is a waiting period — usually one to eight years — called Qi Yun (起运), literally "starting the luck". It is computed, not guessed: from the hours between your birthday and the next (or previous) solar term, scaled by a classic formula — three days count as one year (each day as four months), and every two-hour double-hour counts as ten days. The result is a precise launch date for your first decade.
Take the chart we keep returning to — born 15 March 1995. Its Qi Yun lands at 3 years old, starting on 21 March 1998 (nominal age), with a retrograde direction, which makes the first chapter 戊寅 and the parade march backward through the sixty-cycle. Notice the precision: the formula does not round to a neat birthday. It produces a date, the way an almanac produces an eclipse time.
Why the direction flips
Whether your chapters march forward or backward through the sixty-cycle is fixed by one classic rule: Yang-stem years push male charts forward and Yin-stem years push them backward — and the reverse in female charts. This is why two people born the same day but of different sexes receive different life chapters: the direction of the weather changes with the gender convention. Some find the rule arbitrary; the tradition treats it as bedrock. Either way, it is deterministic and checkable in a minute: the chart page shows the direction and the reasoning.
Age is a convention; luck is a framework
The nominal age has nothing to do with your calendar age being "real" or "fake" — it is simply the unit the framework is written in. And once you know the unit, the timeline reads cleanly: 3–12, 13–22 and onward, decade by decade, each with its own stem, branch and theme. Use nominal years as the tradition does — as the rails the Da Yun train runs on.
Find your own Qi Yun date — the chart page computes your launch age to the day, with direction and reasoning shown.
Related reading
- Understanding Da Yun — the ten-year chapters this clock switches on
- Critical years — the years that ring your chart inside the chapters
- The Four Pillars, explained — what the timeline is built from