Kaigen is a distinctive boys' name in United States, ranking #9182 in 2011 with 8 recorded births. This places Kaigen in the bottom 36% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2010 with 8 births ranking #9231. In 2011, approximately 1 in every 237,374 boys born was named Kaigen. FALLING Recent data shows the name is currently falling.