Seiji is a distinctive boys' name in United States, ranking #9694 in 2024 with 8 recorded births. This places Seiji in the bottom 32% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2007 with 19 births ranking #4951. In 2024, approximately 1 in every 214,414 boys born was named Seiji. FALLING Recent data shows the name is currently falling.