The vocal range of a countertenor is equivalent to that of the female contralto or mezzo-soprano voice types. A trained countertenor will typically have a vocal center similar in placement to that of a contralto or mezzo-soprano. Particularly in the British choral tradition, the terms male soprano and male alto serve to identify men who rely on falsetto vocal production, rather than the modal voice, to sing in the soprano or alto vocal range. Elsewhere, the terms have less universal currency.

Countertenors often are natural baritones or tenors, but rarely use this vocal range in performance.

The term first came into use in England during the mid-seventeenth century, and was in wide use by the late seventeenth century. However, the use of adult male falsettos in polyphony, commonly in the alto range, was common in all-male sacred choirs for some decades previous, as early as the mid-sixteenth century. Modern-day ensembles such as the Tallis Scholars and the Sixteen maintain the use of male altos in period works. During the romantic period, the popularity of the countertenor voice waned and few compositions were written with that voice type in mind.

Within the countertenor voice type category are three generally recognized subcategories: the sopranist or “male soprano,” the haute-contre, and the castrato.