Baby Gender Prediction at 9 Weeks
At 9 weeks, you're in the final stretch of the first trimester's early phase. Gender prediction is still unreliable — the external genitalia are only beginning to differentiate and won't show clear signs on ultrasound for several more weeks.
Your Baby at 9 Weeks
- ✦Baby measures about 23mm — the size of a grape
- ✦The tail is gone and baby looks more human
- ✦Joints in the arms and legs are forming
Gender Prediction Methods at 9 Weeks
Nub Theory
The genital tubercle is present at 9 weeks but hasn't angled distinctively yet. Nub theory requires a clear angle measurement — not possible this early.
Skull Theory
Skull theory requires visible bone structure differences that don't exist yet at 9 weeks. Wait until 12+ weeks.
Chinese Gender Calendar
The Chinese Gender Calendar can always be calculated and gives an instant result — but controlled studies show it performs at roughly 50% accuracy.
AI Ultrasound Analysis
AI analysis at 9 weeks is possible but gives roughly 60-65% accuracy. The markers are beginning to emerge but aren't distinctive enough for confident predictions.
Get Your AI Gender Prediction
Upload your 9-week scan for an early AI read — and come back at 12 weeks for a significantly more accurate prediction.
Upload Your 9-Week Scan →Frequently Asked Questions
Can you tell the gender of a baby at 9 weeks?
Technically possible but not reliably. At 9 weeks, the external genitalia are just beginning to differentiate. Most gender prediction methods don't become useful until 11-13 weeks.
How accurate is gender prediction at 9 weeks?
About 60-65% with AI analysis, 50% with the Chinese Gender Calendar. Meaningful accuracy starts around 12+ weeks when nub and skull theory become applicable.
What does a boy/girl look like on an ultrasound at 9 weeks?
At 9 weeks, a scan shows a recognisably human foetus but the genital area appears as a small undifferentiated bud — indistinguishable between boys and girls.