Cynthia is a moderately popular girls' name in United States, ranking #428 in 2011 with 733 recorded births. The name reached its all-time peak in 1996 with 3,189 births ranking #101. Since 1996, the popularity has decreased by 77.0%. In 2011, approximately 1 in every 2,399 girls born was named Cynthia. FALLING Recent data shows the name is currently falling.