Jack Endino (born Michael M. Giacondino;[1] 1964) is an American producer and musician based in Seattle, Washington.

Long associated with Seattle label Sub Pop and the grunge movement, Endino worked on seminal albums from bands including Mudhoney, Soundgarden and Nirvana.

His skill and low fees meant that he was soon an engineer of choice for up-and-coming Seattle grunge bands, and in 1988, he recorded Nirvana's debut album Bleach in 30 hours for $606.17, using reel-to-reel 8-track machine.

Largely because of the success of albums like Soundgarden's Screaming Life and Nirvana's Bleach in the mainstream, the resulting raw, unpolished sound is still seen as a defining characteristic of the grunge movement.

Since 2015, Endino has played lead guitar in Seattle rock band MKB ULTRA, and also with the improv-psych trio Beyond Captain Orca.