Kainalu first appears in the U.S. registration record in 1991. Its popularity climbed over the following decades. In 2003, 32 babies received the name (ranked #3022). Today it sits well outside the top 1,000 (around #5183), with roughly 18 babies named Kainalu each year. Kainalu's usage has held roughly steady recently. In total, around 652 babies have been registered with this name since 1880.