About This Site

What this site is

Chinese Gender Calendar exists to do one thing properly: take two dates, convert them to the Chinese lunar calendar correctly, and show you what the traditional birth chart says. No account, no paywall, no popups.

What we will not claim

We will not tell you the chart is accurate, because it is not. Independent research puts it at around 50 percent, the same as guessing. Plenty of sites in this niche imply otherwise, usually with a made-up accuracy percentage. We would rather you enjoy the tradition knowing exactly what it is.

We are not medical professionals and nothing here is medical advice. If you need to know your baby’s sex, that is a conversation with your midwife or doctor.

How the calculator is built

The part that is genuinely hard here is the lunar conversion, and it is where most calculators quietly go wrong. Ours is built on a generated table of lunar-year data covering 1900 to 2100, and it is verified against an independent reference implementation for every single day in that range, more than 73,000 dates, as part of the test suite.

Specifically, it handles:

• Traditional age reckoning, where you are one at birth and gain a year at Chinese New Year rather than on your birthday.
• The New Year cutoff, so a conception in early February lands on the correct side of the age boundary.
• Leap months, including flagging when your conception date falls inside one.
• The complete chart, lunar ages 18 through 45, with no missing rows.

The whole calculation runs in your browser. Your dates are never sent anywhere, logged, or stored.

Where the chart data came from

Published versions of the chart disagree with each other more often than you would expect, including charts sitting on the same site as a calculator that contradicts them. The table used here was cross-checked cell by cell against multiple independent sources, and every cell is covered by an automated test.

Corrections

If you spot something wrong (a date that converts incorrectly, a chart cell that disagrees with a source you trust, or a claim that overstates the evidence), please tell us at chinesegendercalendar727@gmail.com. We would rather fix it than defend it.