"Don't Stop Believin'" is a song by American rock band Journey, originally released as the second single from their seventh album Escape (1981). It became a number 9 hit on the Billboard Hot 100 on its original release. In the United Kingdom, the song was not a Top 40 hit on its original release; however, it reached number 6 in 2009.

Mike DeGagne of AllMusic has described "Don't Stop Believin'" as a "perfect rock song" and an "anthem", featuring "one of the best opening keyboard riffs in rock." It is the best-selling digital track from the 20th century with over 7 million copies sold in the United States. The song was covered by the cast of Glee.

While most popular songs have a refrain that is repeated several times throughout the song, the true chorus to "Don't Stop Believin'" (as well as first mention of its title) is not heard until the end of the song, with only 0:50 left. The song's writers designated the musically similar sections before the chorus as the "pre-chorus." The song's structure is:

The song is played in the key of E major at a tempo of 118 beats per minute. The vocal range is E₃–C#₅. The chord progression, played by the piano in the introduction and continued throughout most of the song, is eight chords long, following a I-V-vi-IV-I-V-iii-IV progression.

The title of the song came from something keyboardist Jonathan Cain's father frequently told him when he was a struggling musician living on Los Angeles' Sunset Boulevard ready to give up because he was not having success in the music industry. Each time he would call home in despair, his father would tell him, "Don't stop believing or you're done, dude."

While the lyrics mention being "born and raised in south Detroit", the area that would be considered south Detroit is actually the Canadian city of Windsor. Steve Perry has said, "I tried north Detroit, I tried east and west and it didn't sing, but south Detroit sounded so beautiful. I loved the way it sounded, only to find out later it's actually Canada."

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