Kay is a distinctive girls' name in United States, ranking #3632 in 2015 with 43 recorded births. The name reached its all-time peak in 2002 with 79 births ranking #2129. Since 1996, the popularity has decreased by 35.8%. In 2015, approximately 1 in every 41,504 girls born was named Kay. FALLING Recent data shows the name is currently falling.