Caius has been given to about 2,329 people in the United States since 1880. It was most common in 2025, which makes it a current name.
Caius ranks 927th among American boys in 2025, with 254 born that year. Its best year was 2025, when 254 babies were given the name, ranking 927th. The typical living American called Caius is about 7 years old today. It is relatively most common in Maryland, where it accounts for 0.02% of births.
Source: US Social Security Administration, national and state name files, 2025 release, and the Office for National Statistics for England and Wales. Etymology researched and written by our editors. Living-population and median-age figures are our own estimates, described in the methodology.