Kei is a distinctive boys' name in United States, ranking #4815 in 1997 with 13 recorded births. This places Kei in the top 45% 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 160.0%. In 1997, approximately 1 in every 145,007 boys born was named Kei. FALLING Recent data shows the name is currently falling.