Rei is a distinctive boys' name in United States, ranking #7940 in 1997 with 7 recorded births. This places Rei in the bottom 27% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2025 with 35 births ranking #3363. In 1997, approximately 1 in every 269,299 boys born was named Rei. RISING Recent data shows the name is currently rising.