The name Kaja reached its peak in 2009, with 25 registrations (ranked #5620). It had been quietly building for over half a century before that, first appearing in records in 1957. Since the peak, the name has eased to well outside the top 1,000 (around #7449) today, averaging about 16 new babies per year. Kaja's usage has held roughly steady recently. Across all years on record, approximately 694 American babies have carried this name.