The Hungarian-born Kálmán displayed his musical talent during childhood and began studying the piano at an early age, but he was forced to abandon the instrument because of chronic neuritis. He entered the Budapest Academy of Music in 1900 as a composition student, pursuing a law degree at the same time. His classmates included Béla Bartók and Zoltán Kodály. Kálmán was published as a music critic from 1904 through 1908, and his early works earned him the Franz Josef Prize of Budapest in 1907. Kálmán started out as a composer of serious music, but his cabaret songs proved extremely popular and he began moving toward lighter music in 1907. The following year, he wrote his first operetta, The Gay Hussars, which was a hit throughout Europe and the United States. Its success in Vienna led Kálmán to make his home in the Austrian capital. He spent his most productive years in Vienna, writing an enviable string of very high-quality operettas, which were characterized not only by gorgeous melodies and delectable choruses but startlingly vivid librettos. This was a frequent failing of many other operetta composers; for example, Johann Strauss II, for all of his skills as a composer, had virtually no sense at all when it came to choosing librettos, which has made it impossible to revive most of his operettas. His work combined the most pleasing and sophisticated elements of Viennese operetta with the richly melodic, romantic Hungarian style of writing pioneered by Franz Liszt, not authentic but very enticing to the ear. Wherever possible, he found reason to include this Hungarian and gypsy-style writing in his work, although in later years he also experimented with jazz influences, as in his 1928 operetta Die Herzogin von Chicago. Kálmán's 1912 operetta Der Zigeunerprimas elicited the critical comment from Viennese critic Richard Specht: "His music is fresh and pleasant, full of strength in its natural melodic invention and wholesome maturity. While others grope and experiment, he stands in the rich soil of folk music and hits the mark every time." His best work, well into the early '30s, evoked the golden age of the Viennese waltz while his orchestrations, as he freely admitted, were intended to evoke memories of Tchaikovsky's lushest work. His best operettas, most of which date from the period prior to the forced unification of Austria and Germany in 1938, are filled with memorable songs and choruses. Kálmán's main contribution as a composer was as a creator of works that emphasized the choruses, as opposed to dance material, which was largely absent from his operettas. With the American composer Herbert Stothart (who was to become a mainstay of the MGM music department in the 1930s and 1940s), Kálmán collaborated on the 1927 musical Golden Dawn, which utilized lyrics by Oscar Hammerstein. Kálmán also found occasion to experiment in new media, writing the score to a filmed operetta, entitled Ronny, in 1931.
Kálmán left Austria in 1938 upon the Anschluss with Germany. From 1939 until 1940, he resided in Paris and following the German conquest of France, he moved to the United States. He renounced his Hungarian nationality after that country's government entered into a formal alliance with Nazi Germany. He completed one new operetta, Marinka, in 1945. His son, Charles Emmerich Kálmán, is also a successful composer of musicals and completed the elder Kálmán's final work, Arizona Lady, in 1954.
Kálmán's works are still occasionally performed at the end of the twentieth century in Germany and Austria and recordings exist of several of them, primarily dating from the early '70s. Singers of the caliber of Nicolai Gedda and Anneliese Rothenberger have performed and recorded the most popular of these, principally for German-speaking audiences, although EMI has also released them in England and America.