Baby Gender Prediction at 11 Weeks
At 11 weeks, gender prediction becomes genuinely possible for the first time. The nub — the genital tubercle — is starting to angle, which means a trained eye (or AI) can begin making educated predictions with increasing accuracy.
Your Baby at 11 Weeks
- ✦Baby measures about 41mm — the size of a fig
- ✦Fingers and toes are fully separated
- ✦Baby's face is clearly forming with defined features
Gender Prediction Methods at 11 Weeks
Nub Theory
Nub theory starts working at 11 weeks. If the nub angles upward at more than 30 degrees, it suggests a boy. A horizontal or downward-angled nub suggests a girl. Accuracy is around 70-75% at this stage.
Skull Theory
Skull theory is just becoming applicable at 11 weeks. The differences are subtle and hard to read — most practitioners prefer to wait until 12-13 weeks for skull analysis.
Chinese Gender Calendar
The Chinese Gender Calendar gives an instant result based on your lunar age and conception month — a fun addition to your prediction toolkit.
AI Ultrasound Analysis
AI analysis at 11 weeks combines nub angle detection with other early markers, reaching around 75-80% accuracy. This is when our AI predictions start becoming meaningfully useful.
Get Your AI Gender Prediction
Upload your 11-week scan — our AI analyses the nub angle and other early markers to give you a prediction with ~75% accuracy.
Upload Your 11-Week Scan →Frequently Asked Questions
Can you tell the gender of a baby at 11 weeks?
Yes — 11 weeks is the earliest point where gender prediction starts becoming reliable. Nub theory begins to apply, and AI analysis can combine multiple markers for around 75% accuracy.
How accurate is gender prediction at 11 weeks?
Around 70-75% for nub theory and 75-80% for AI analysis at 11 weeks. This is a significant jump from previous weeks and gets better with each passing week.
What does a boy/girl look like on an ultrasound at 11 weeks?
At 11 weeks, the nub (genital tubercle) is visible on ultrasound. In boys, it tends to angle upward; in girls it remains more horizontal. The difference is subtle but detectable by trained analysis.