Un-Break My Heart - Composition

Composition

Produced by David Foster, "Un-Break My Heart" is an R&B power ballad with a length of four minutes and twenty seconds. The song's theme alludes to a "blistering heartbreak" in which Braxton begs a former lover to return and undo the pain he has caused. According to sheet music published by Realsongs at Musicnotes.com, "Un-Break My Heart" is composed in the key of B minor and is set in time signature of common time with a moderately slow tempo of 55 beats per minute. Braxton's vocal range spans from the low-key of D₃ to the high-note of D₅. David Willoughby, author of The World of Music (2009) said that a few phrases such as "Don't leave me in all this pain" are sufficient to reveal the "sadness and the longing" in the song.

The song was remixed by several DJs such as Hex Hector and Soul Solution. As noted by Jose F. Promis of Allmusic, the song "in its original form, was a massive adult contemporary and pop hit, and, with its larger-than-life chorus, worked equally well as an unstoppable dance number, even if the vocals were never re-recorded." The "Soul-Hex Vocal Anthem" remix, with a length over nine minutes, was influenced by tribal house music; while the "Classic Radio Mix" is a piano-driven house edit. A Spanish version of "Un-Break My Heart" titled "Regresa a Mi" was included as a bonus track on Secrets. musicOMH contributor Uma Uthayashanker considered it "an easy listen" version "that encapsulates the passion and meaning of the original but opens it up to a wider audience."