About

For centuries, the Chinese Gender Chart (found in the Qing Dynasty imperial tomb) has been used by expectant parents to guess the sex of their unborn child. Unlike modern genetics, this method relies on the mother's Lunar Age and the Lunar Month of conception. A common error in online tools is using the standard Gregorian age (Western calendar), which often leads to incorrect readings of the chart.

This tool performs the necessary astronomical conversion automatically. In the traditional Chinese system, a person is considered 1 year old at birth, and age increments on the Chinese New Year, not the birthday. By cross-referencing the corrected Lunar variables against the digitized matrix of the ancient manuscript, we generate a prediction purely for entertainment purposes.

Formulas

The calculation relies on the coordinate system (A, M) of the Qing Palace Chart:

Gender = Matrix[ Age_lunar , Month_lunar ]

Where:

Age_lunar: (Current Year − Birth Year) + 1 (adjusted for CNY).
Month_lunar: The ordinal number of the month in the lunisolar calendar at the time of conception.

Reference Data

Lunar Age	Month 1	Month 2	Month 3	Month 4	Month 5
18	Girl	Boy	Girl	Boy	Boy
19	Boy	Girl	Boy	Girl	Girl
20	Girl	Boy	Girl	Boy	Boy
21	Boy	Girl	Girl	Girl	Girl
25	Girl	Boy	Boy	Girl	Girl

Frequently Asked Questions

There is no scientific basis for the chart; it is a statistical curiosity from ancient folklore. While some claim accuracy rates up to 90%, scientific studies suggest it is about 50% accurate-essentially the same as a coin toss.

This calculator handles that variable. If your birthday falls before the Chinese New Year in your birth year, you are effectively one year older in the lunar system compared to someone born days later. This shift can completely change the prediction result.

For IVF (In Vitro Fertilization), you should use the date of conception (retrieval/fertilization) or adjust based on the transfer date minus the embryo age (3 or 5 days). The biological sex is determined at the moment of fertilization.