Kalmar, a native of New York City, left school at an early age and began working in vaudeville.

[1] He appeared on stage as a magician, comedian and dancer before switching to songwriting, after a knee injury ended his performing career.

Together, they wrote the musical score for the Marx Brothers' stage production of Animal Crackers (1928) and subsequent film version.

Kalmar's partnership with Ruby was portrayed in the 1950 Metro-Goldwyn-Mayer musical Three Little Words, starring Fred Astaire and Red Skelton.

Kalmar did, however, occasionally work with Oscar Hammerstein II, Ted Snyder and other songwriters.