Baby Gender Prediction at 16 Weeks
At 16 weeks, many parents find out the gender at their anomaly scan or a private 3D scan. The genitalia are now well-developed enough that even a standard ultrasound can often reveal the sex clearly.
Your Baby at 16 Weeks
- ✦Baby is about 115mm — the size of an avocado
- ✦Baby is making sucking and swallowing motions
- ✦Eyebrows and eyelashes are starting to grow
Gender Prediction Methods at 16 Weeks
Nub Theory
By 16 weeks the nub has largely developed into the genitalia — nub theory transitions into direct genital observation. Accuracy from a good image is around 85-90%.
Skull Theory
Skull theory gives around 80% accuracy at 16 weeks. The characteristic shapes are clearly established.
Chinese Gender Calendar
The Chinese Gender Calendar is always a quick and popular method for a fun early guess alongside your scan results.
AI Ultrasound Analysis
AI analysis at 16 weeks reaches around 85-90% by examining the developing genitalia directly alongside other anatomical markers.
Get Your AI Gender Prediction
Upload your 16-week scan — this is a prime window for gender prediction and our AI can often give you a confident answer.
Upload Your 16-Week Scan →Frequently Asked Questions
Can you tell the gender of a baby at 16 weeks?
Yes — 16 weeks is when many parents learn their baby's gender. The genitalia are well enough developed to be seen on most ultrasound scans.
How accurate is gender prediction at 16 weeks?
Around 85-90% from direct genital observation and AI analysis. This is a significant accuracy milestone compared to earlier weeks.
What does a boy/girl look like on an ultrasound at 16 weeks?
At 16 weeks, a boy's penis and scrotum are clearly forming and often visible on ultrasound. A girl's labia are defined and the absence of scrotal tissue is the clearest indicator.