Kei is a distinctive boys' name in United States, ranking #6284 in 2025 with 14 recorded births. The name reached its all-time peak in 2015 with 33 births ranking #3401. Since 1996, the popularity has increased by 180.0%. In 2025, approximately 1 in every 122,005 boys born was named Kei. FALLING Recent data shows the name is currently falling.