Namesakes
American Presidents:
1 president
Calvin Coolidge 1923-1929 
Fictional Characters from Television:
1 character
Calvin Owens 2007 Greek
Hall-of-Famers:
2 football, 1 baseball, 1 basketball
(football) Cal Hubbard 1963
(basketball) Calvin Murphy 1993
(baseball) Cal Ripken Jr. 2007
(football) Calvin Johnson 2021
Most Valuable Players:
1 winner
Cal Ripken Jr. 1983; 1991 baseball
Nobel Prize Winners:
1 medicine
(medicine) Edward Calvin Kendall 1950
Notable Actors and Entertainers:
1 presenter
Dr. Phil (a.k.a. Calvin) 1950-
Notable Artists:
1 fashion designer
Calvin Klein 1942-
Notable Athletes:
1 baseball, 1 basketball
(basketball) Calvin Murphy 1948-
(baseball) Cal Ripken Jr. 1960-
Notable Musicians:
2 musicians, 1 singer
Bobby Bland (a.k.a. Calvin) 1930-2013
Calvin "Snoop Dogg" Broadus Jr. 1971-
Calvin Harris 1984-
Olympic Medalists:
1 bronze, 1 bronze/silver, 1 gold, 1 gold/bronze
(bronze/silver) Calvin Bricker 1908; 1912 long jump
(gold) Calvin Fowler 1968 basketball
(gold/bronze) Calvin Smith 1984; 1988 4x100 m relay; 100 m
(bronze) Calvin Davis 1996 400 m hurdles
Other Fictional Characters:
1 character
Calvin 1985 comic strip
Rock and Roll Hall-of-Famers:
2 musicians
Bobby Bland (a.k.a. Calvin) 1992
Calvin Simon 1997 Parliament-Funkadelic