"Brand New Key" is a pop song written and sung by American folk music singer Melanie.

So we pulled into the McDonald's and I got the whole works... the burger, the shake, and the fries... and no sooner after I finished that last bite of my burger… that song was in my head.

[3] Melanie has acknowledged the possibility of detecting sexual innuendo in the lyrics, but has denied any deeper meaning: [The song], "Brand New Key", I wrote in about fifteen minutes one night.

Country singer Deana Carter covered the song on her 1999 top-10 album Everything's Gonna Be Alright.

On August 1, 2018, at Daryl's House Club in Pawling, New York, Melanie joined Rundgren onstage to sing "Brand New Key".

The 2006 American Idol runner-up, Katharine McPhee, covered the song as the bonus track on her 2010 Unbroken album.

[25] Melanie's version is heard in the 1997 film Boogie Nights as Dirk Diggler (Mark Wahlberg) has his "audition" with Rollergirl (Heather Graham) in front of Jack Horner (Burt Reynolds).

[27] During the 16th season of American Idol, contestant Maddie Poppe performed the song during the Top 24 elimination round.

[28] The song is played during the "Apocalypse DJ" running sketch portion of the third episode of the 2022 The Kids in the Hall revival series.

[30] On the October 17, 2016, episode of singing competition television show The Voice, Team Miley (Cyrus) contestants Darby Walker and Karlee Metzger performed the song in a Battle round.

In the first online episode of the Comeback Stage of the singing competition television show The Voice, no-chair reject Klea Olson performed the song as part of a Battle round against fellow Team Bebe (Rexha) members Nathan and Chesi Arnett, who performed the song "Tulsa Time".