Kei is a distinctive boys' name in United States, ranking #4693 in 2004 with 18 recorded births. This places Kei in the top 35% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2015 with 33 births ranking #3401. Since 1996, the popularity has increased by 260.0%. In 2004, approximately 1 in every 110,267 boys born was named Kei. FALLING Recent data shows the name is currently falling.