Kaelen is a unique and modern given name of Irish origin, derived from the surname Caolán. It is composed of the elements "caol" meaning "slender" or "slim", and "án" which is a diminutive suffix. The name gained popularity in recent times as parents sought distinctive names for their children. In English-speaking countries, Kaelen is often seen as an alternative spelling to Caelan or Kaelin, but it stands on its own with its distinct Irish roots.
The name Kaelen experienced a notable peak in popularity between 1994 and 2008, with over 23 births each year during this period. However, since 2009, the number of babies named Kaelen has consistently declined, dropping below 20 births per year from 2014 onwards, and reaching a low of 9 births in 2023. Overall, there were 709 babies named Kaelen between 1990 and 2023.