[1] He co-wrote, produced, and mixed the 2014 Diamond certified (10× platinum) single "All About That Bass" by Meghan Trainor which spent eight weeks at No.

In 2018, the song was named the 67th Biggest Hot100 Hit of All-Time, by Billboard, seated between The J. Geils Band's "Centerfold" (66) and John Lennon's "(Just Like) Starting Over" (68).

After graduating from Owings Mills High School, he attended Berklee College of Music and studied Film Scoring.

In 1991, Kadish transferred from Berklee to the University of Maryland, College Park where he designed his own major, Music Management, through the Individual Studies Department.

Throughout the mid-1990s, Kadish toured the East Coast as a solo, acoustic artist, opening for Hall & Oates, Vertical Horizon, Dave Matthews Band, Jeff Beck, SR-71, Marcy Playground, Everything, and others.

In 2012, Kevin co-wrote and produced "Crazy For You" with Ross Lynch, "Rooftops" with American Idol winner Kris Allen.

"[7][8] In 2015, Kadish worked with artists such as Garth Brooks, Daniel Powter, Miranda Lambert, O.A.R., A Great Big World, Jennifer Lopez, Fifth Harmony, Steven Tyler (Aerosmith), and others.

[citation needed] In 2016, Kadish partnered with producer and songwriter Nathan Chapman (Taylor Swift, Keith Urban, Lady Antebellum, etc.)

Other songwriting credits include work with and for Michelle Branch (Warner Bros.), Taylor Hicks (Arista), Joe Jonas (Hollywood), Skillet (Lava/Atlantic), BC Jean (J Records), Tal Bachman (Sony), Bif Naked (Lava/Atlantic), Lucy Woodward (Atlantic), Evan Taubenfeld (Sire/Warner Bros.), Nikki Sixx (Mötley Crüe), Steve Perry, Kris Allen (Jive Records), Billy Currington (Mercury Nashville Records), Canaan Smith (Universal Nashville), Plain White T's, Colt Ford, Muni Long, Ben Burgess, Brian Kelley from the band FGL, etc.

He contributed acoustic guitars and backing vocals, and co-wrote the Miley Cyrus song "Two More Lonely People" for her album Can't Be Tamed.