Kiffmeyer was born in California on July 11, 1969. His first exposure in the punk scene was as the drummer of the band Isocracy. The group was popular in the East Bay, and mainstays at the famed club, 924 Gilman Street.
Kiffmeyer is most well known for his time in Green Day; after Isocracy broke up, he joined Mike Dirnt and Billie Joe Armstrong to form Sweet Children, which was later renamed to Green Day. Because of his experience and knowledge of the underground community, Kiffmeyer was able to get the young band on its feet by placing calls to friends, among them prominent figure of the East Bay Larry Livermore. The first few performances took place at Contra Costa College, where Kiffmeyer was a journalism student. On the strength of an early performance, Livermore vowed to release a Green Day record on his Lookout! Records. The group's first full-length effort, 39/Smooth, would feature a Kiffmeyer original, "I Was There", whcih documented the band at that place in time. Being a fan of Ozzy Osbourne, it was he who inspired the mini-covers of some famous songs, such as "I Don't Know" by Ozzy Osbourne and "Sweet Home Alabama" by Lynyrd Skynyrd during the bridge of "Disappearing Boy," a practice that is still carried out today.
In 1990, he attended college at Humboldt State University in Arcata, California. While Kiffmeyer was attending college, Green Day members Billie Joe Armstrong and Mike Dirnt accepted drummer Tré Cool into the band, which Kiffmeyer "graciously accepted". Kiffmeyer later joined the band The Ne'er Do Wells, leaving abruptly in 1994. Following a stint with punk band The Ritalins, he became the manager of The Shruggs until their split. In 1998 he was the executive producer of The Great Lost Trouble Makers Album by The Troublemakers, a garage band from Sacramento, California.
He now lives in San Francisco and is married to experimental filmmaker and San Francisco State University professor Greta Snider. He works as a Director of Photography, specializing in green screen and producing mainly commerical work.
On April 16, 2015, Kiffmeyer joined Billie Joe Armstrong and Mike Dirnt on stage during a Green Day concert at The House of Blues Cleveland, Ohio where the trio performed as Sweet Children, playing songs that they had not performed since the 1990's including "Sweet Children", "I Was There", and "Dry Ice."