“Shape of My Heart” is a song by American boy band, Backstreet Boys, it was written and produced by Max Martin and Rami, and co-written by Lisa Miskovsky. It was released on October 3, 2000 as the lead single from the band’s fourth studio album, Black & Blue.

The song earned a Grammy Award nomination during the 44th Grammy Awards for Best Pop Performance by a Duo or Group with Vocals.

Due to the success of rival boy band NSYNC’s album No Strings Attached selling over 2.4 million copies in its first week, there were high expectations from industry experts and fans that the Backstreet Boys' next album Black & Blue would break the first week sales of No Strings Attached. “Shape of My Heart” was widely anticipated as the lead single of Black & Blue, which would follow their previous singles “Quit Playing Games (with My Heart)”, “Everybody (Backstreet’s Back)”, and “I Want It That Way”.

Shape of My Heart" is stated to be “the sound of a boy band becoming a group of men”. It consists of a bubblegum chorus, clean pop structure, along with various vocal harmonies from Max Martin’s production. It also contains soft-pop guitar, low-key percussion, and a lyrical emphasis on the reflection of past mistakes.

The song is performed in D major with a key switch to E major at the third chorus.