How the Chinese gender calendar works
The Chinese gender calendar, also called the Chinese gender chart, is a lookup table that claims to predict a baby’s sex from two things: the mother’s lunar age at conception and the lunar month in which the baby was conceived.
Lunar age
In the traditional Chinese system a baby counts as one year old at birth and gains a year at each Lunar New Year, not on a birthday. That makes a mother’s lunar age at conception usually a year or two higher than her age in years. Our predictor works it out for you from the two dates you enter.
Lunar month
The Chinese calendar follows the moon, so its months start on different dates from the ones on a wall calendar. For example, June 20, 2026 falls in the fifth lunar month.
Reading the chart
The chart has one row for each lunar age (we cover 18 to 45) and one column for each lunar month. Each cell says boy or girl. A mother born on March 10, 1995 who conceives on June 20, 2026 has a lunar age of 32 and a lunar month of 5, and the chart gives girl.
Where it comes from
Stories say the chart is more than 700 years old, but none of them has been verified. Different websites publish different versions of the chart, so two calculators can disagree for the same dates.
How accurate is it?
Studies that have tested it found it no better than a coin toss. That is what you would expect, since any method that picks boy or girl will be right about half the time by chance. Treat it as a fun tradition.