Kj is a distinctive boys' name in United States, ranking #7921 in 2007 with 10 recorded births. This places Kj in the bottom 45% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2021 with 21 births ranking #4705. In 2007, approximately 1 in every 207,524 boys born was named Kj. FALLING Recent data shows the name is currently falling.