The Chinese Gender Predictor, also known as the Chinese Birth Chart or Chinese Pregnancy Calendar, is an ancient method said to predict a baby's gender based on the mother's lunar age at conception and the lunar month of conception. According to legend, this chart was discovered in a royal tomb near Beijing over 700 years ago and was used by the Chinese imperial family to ensure male heirs.
While there's no scientific evidence supporting its accuracy (it's essentially 50/50, like any gender prediction without ultrasound or genetic testing), the Chinese Gender Chart remains incredibly popular for fun baby gender guessing. Many expectant parents enjoy using it as an entertaining way to speculate about their baby's gender before the official reveal.
The Chinese Gender Predictor uses two key inputs to make its prediction:
The calculation to determine lunar age is approximately:
Where the adjustment depends on whether the conception occurred before or after the Chinese New Year (which falls between January 21 and February 20).
Let's walk through a prediction for a mother born on March 15, 1990, who conceived in July 2024:
Step 1: Calculate Western Age at Conception
In July 2024, she would be 34 years old (Western age).
Step 2: Convert to Lunar Age
Since she was born after Chinese New Year in 1990, her lunar age is 34 + 1 = 35.
Step 3: Determine Lunar Month
July 2024 in the Gregorian calendar corresponds to the 6th lunar month.
Step 4: Consult the Chart
Looking at the intersection of lunar age 35 and lunar month 6 on the traditional Chinese Gender Chart, the prediction would be... Girl!
| Lunar Age | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 18 | G | B | G | B | B | B | B | B | B | B | B | B |
| 19 | B | G | B | G | G | B | B | G | B | B | G | G |
| 20 | G | B | G | B | B | B | B | B | B | G | B | B |
| 21 | B | G | G | G | G | G | G | G | G | G | G | G |
| 22 | G | B | B | G | B | G | G | B | G | G | G | G |
| 23 | B | B | B | G | B | B | G | G | G | B | B | G |
| 24 | B | G | G | B | B | G | B | G | B | B | G | G |
| 25 | G | B | G | B | G | B | G | B | G | B | B | B |
| 26 | B | B | B | B | B | G | B | G | G | B | G | G |
| 27 | G | G | B | B | G | B | G | G | B | G | B | B |
| 28 | B | B | B | G | G | B | G | B | G | G | B | G |
| 29 | G | B | G | G | B | G | G | B | G | B | G | G |
| 30 | B | B | G | B | G | B | B | B | B | B | B | B |
B = Boy, G = Girl (Chart continues for ages 18-45)
According to Chinese folklore, the original gender prediction chart was buried in a royal tomb near Beijing during the Qing Dynasty (1644-1912). Some legends place its origin even earlier, claiming it was created by Chinese scientists over 700 years ago based on the I Ching, Five Elements theory, and Yin-Yang principles.
The chart supposedly spent years in the keeping of palace eunuchs before eventually making its way to Austria and then England. In the 1970s, a Chinese scholar allegedly brought a copy to the Western world, and it has since spread globally through books, websites, and word of mouth.
Whether any of this history is accurate is debatable—there's no verified historical documentation. What's certain is that the chart has become a beloved tradition for expectant parents around the world.
From a scientific standpoint, the Chinese Gender Predictor has roughly 50% accuracy—the same as random chance. Several studies have tested the chart's predictions against actual birth outcomes:
| Study | Sample Size | Accuracy Found |
|---|---|---|
| University of Michigan (1999) | ~2.8 million births | 50.2% |
| Swedish Study (2010) | ~3 million births | 50.1% |
| Various Informal Surveys | Thousands | 48-53% |
The only reliable methods for determining baby gender are:
The Chinese lunar calendar differs from the Western Gregorian calendar in several important ways:
This means your Chinese lunar age can be 1-2 years higher than your Western age, depending on your birthday and the current date.
While the chart isn't scientifically valid, many people enjoy using it for:
Is this really accurate? No, it's approximately 50% accurate—the same as a coin flip. It's for entertainment only.
Why do some people swear it worked for them? With a 50% accuracy rate, it will be correct for half of all pregnancies. This can create strong confirmation bias—people remember when it works and forget when it doesn't.
What if I don't know my exact conception date? Use an estimate. Most pregnancies last about 40 weeks from the last menstrual period, so conception is typically about 2 weeks after that date.
Does this work for IVF or other assisted reproduction? The chart uses the same logic regardless of conception method, but there's no evidence it's any more accurate for any particular situation.
Can I use this to choose my baby's gender? While some couples try to time conception based on the chart, there's no scientific evidence this affects outcomes. Baby gender is determined by the sperm cell that fertilizes the egg.
This Chinese Gender Predictor is provided for entertainment purposes only. It has no scientific basis and cannot accurately predict a baby's gender. The chart's accuracy is equivalent to random chance (approximately 50%).
Gender determination in humans is biological: it depends on whether an X-bearing or Y-bearing sperm cell fertilizes the egg. No calendar, chart, diet, or timing method can reliably influence or predict this outcome.
Do not make any medical, financial, or life decisions based on this prediction. If you need to know your baby's gender for medical or personal reasons, please consult with your healthcare provider about appropriate testing options.
This tool is meant to be a fun way to engage with pregnancy excitement and cultural traditions—nothing more. Enjoy it in that spirit!