Rei is a distinctive boys' name in United States, ranking #6066 in 2004 with 13 recorded births. This places Rei in the top 46% 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 2004, approximately 1 in every 152,677 boys born was named Rei. RISING Recent data shows the name is currently rising.