"Invincible" is a song by American singer Kelly Clarkson from her seventh studio album, Piece by Piece (2015). It was written by Sia, Jesse Shatkin, Steve Mostyn, and Warren "Oak" Felder. Produced by Shatkin, the track is an orchestral synthpop anthem about self-empowerment. "Invincible" features uncredited vocals from Sia, as well as string arrangements by Oliver Kraus. It was first released as the first promotional single from Piece by Piece on February 23, 2015, but then issued as the album's second single to Hot Adult Contemporary radio stations on May 18, 2015 through RCA Records.

During her Stronger Tour in 2012, Clarkson performed a cover version Sia's single "Breathe Me" (2004). Upon learning of the performance, Sia offered her salutations and revealed that she had been trying to write a song for Clarkson and will continue to submit material. In 2014, Sia revealed that she wrote a song entitled "Invincible" with Jesse Shatkin. And while demonstrating her work with producer Greg Kurstin on NPR, she ended up writing a part of what would be included in the song, which she remarked that no one had cut yet. She, together with Shatkin, who had also previously collaborated with Clarkson as Kurstin's engineer, finished the song towards the end of Clarkson's recording sessions for her seventh studio album, Piece by Piece. Shatkin presented the song to Clarkson, saying "I know you're done recording your album, but we've just wrote this amazing song and we think you could do great on it." Upon hearing their demo, Clarkson decided to record the song, she replied "I think I could too — I want it!".

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