Mack, when "formalized" with the final k, makes an engagingly amiable choice, a far more uncommon alternative to the ubiquitous Max and Jack, with a nice, every-guy feel. Mack entered the popularity list in 2009 for the first time since 1989 and continues to climb. However, it's still far from its peak — it was a Top 100 name in 1900.

Not often heard on girls, although Hillary Scott used it as the middle name for her daughter Betsy in 2018.