Unlike fixed-pitch instruments such as the piano, human singing can stray from a target pitch by as much as a semitone while still being perceived as a single fixed note. This paper presents a study of the difference between target pitch and actualized pitch in natural singing. A set of 50 subjects singing the same melody and lyric is used to compare utterance styles. An algorithm for alignment of idealized template pitch tracks to measured frequency tracks is presented. Specific examples are discussed, and generalizations are made with respect to the types of deviations typical in human singing. Demographics, including the skill of the singer, are presented and discussed in the context of the pitch track deviation from the ideal.