Keilly has been given to about 610 people in the United States since 1880. It was most common in 2011, which makes it a millennial-parent name.
Its best year was 2011, when 48 babies were given the name, ranking 3382nd. The typical living American called Keilly is about 16 years old today.
Source: US Social Security Administration, national and state name files, 2025 release. Etymology researched and written by our editors. Living-population and median-age figures are our own estimates, described in the methodology.