Find out your baby's gender from your 12-week ultrasoundAI-powered · Instant results ✨
Upload your scan, and our AI analyzes the nub theory to predict whether you're expecting a boy or girl — instantly, and just for fun! 🎉
🔮Try It Free First→Upload free · Unlock the full result for $9.99
Example result
The nub angle appears parallel to the spine — a classic girl indicator per nub theory. This is a fun AI prediction, not a medical test.
What is the Nub Theory? 🔬
The nub theory looks at the angle of the genital tubercle (the "nub") at the 12-week scan. An angle above 30° points toward a boy; parallel or below 30° suggests a girl. Our AI analyzes your ultrasound image and applies this theory to give you a fun prediction!
Frequently Asked Questions
🎯 How accurate is it?
Nub theory can be 70–90% accurate when the scan is clear and taken at exactly 12 weeks. Nubbly is a fun prediction tool — not a medical test. For a definitive answer, ask your doctor or wait for an anatomy scan.
🔒 Is my scan safe and private?
Your ultrasound image is only used to generate your prediction and is never shared with third parties or used to train AI models. We take your privacy seriously — your scan is yours alone.
📷 What scan do I need?
You need a standard 2D ultrasound from your 11–13 week dating scan. The scan should show the baby in profile (side view) so the spine and nub are visible. Most NHS/hospital dating scans at 12 weeks work perfectly.
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