Can Ultrasound Tell Who the Father Is? Calculator

by

Compare two intercourse dates with an ultrasound-based conception window to see whether timing favors one possible father or cannot separate them.

Ultrasound timing can sometimes exclude a date, but it cannot prove paternity. A DNA test is needed for proof.
Peer-Reviewed Science
Updated Dec 2025
See Methodology
Did we solve your problem today?

Methodology

The scan date and reported gestational age estimate conception at gestational age minus 14 days. A broad dating margin is applied, and each intercourse date is allowed a five-day sperm-survival window.