Chinese Gender Predictor

Peer-reviewed research shows the Chinese gender predictor is roughly 50% accurate — statistically the same as a coin flip. Despite popular claims of 70-90% accuracy, large studies (notably Villamor et al. 2010 in CMAJ) found no predictive validity. Use it for fun, not for major decisions.

It uses a traditional 24×12 chart where rows represent the mother's lunar age (Gregorian age + 1) and columns represent the lunar month of conception. The chart cell at the intersection predicts boy or girl. The chart is over 700 years old and has cultural significance in Chinese tradition.

In Chinese tradition, a baby is considered 1 year old at birth (counting time in the womb) and turns 2 at the first lunar new year after birth. So lunar age is approximately your Gregorian age plus 1.

The lunar calendar months don't perfectly align with Gregorian months — they shift by about 11 days each year. This calculator uses the Gregorian month as an approximation. For exact lunar calendar conversion, dates near month boundaries may shift by ±1 month.

Anatomy ultrasound at 18-22 weeks is 95-99% accurate when the baby is in a good viewing position. Non-invasive prenatal testing (NIPT) from 10 weeks onward analyses fetal DNA in the mother's bloodstream and is over 99% accurate. Both are widely available through your healthcare provider.

Confirmation bias and survivorship bias. With only two possible outcomes, the chart is 'right' about half the time by chance — and those are the stories that get shared online. People whose chart was wrong rarely write about it.