"Levels" (stylized as "LE7ELS") is a progressive house piece by Avicii. An early instrumental version of the song was first played by Avicii during an appearance on Essential Mix in December 2010, while the final version with Etta James's vocals was first performed at the Ultra Music Festival in March 2011. "Levels" was officially released on 28 October 2011 and peaked at number one in Sweden and on the Dance music charts in United States and became a top ten hit in Austria, Belgium, Bosnia-Herzegovina, Denmark, Germany, Greece, Hungary, Ireland, Italy, the Netherlands, Norway, Switzerland, and the United Kingdom.

"Levels" contains a vocal sample from the 1962 gospel-inspired song "Something's Got a Hold on Me" by Etta James, as written by Leroy Kirkland, Pearl Woods and James. It is the same sample previously used in Pretty Lights's 2006 song "Finally Moving" from his debut album Taking Up Your Precious Time. Flo Rida's single "Good Feeling", which became a worldwide hit in late 2011, was primarily influenced by "Levels" and its Etta James sample.

"Levels" is a progressive house song containing elements of soul, EDM, and house, featuring heavy and high-pitched synths, a quiet bassline and beat. The song is set in common time with a tempo of 126 beats per minute. It was produced in the key of C♯ minor, with a simple chord progression of C#m-E-B-A. It samples lyrics from Etta James' 1962 single, "Something's Got a Hold on Me", only consisting of "Oh, sometimes I get a good feeling, yeah. I get a feeling that I never never never had before. No, no. I get a good feeling, yeah".

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