Spiker was born and raised in Columbus, Ohio and graduated from Upper Arlington High School in 1999. He got his start in music playing the piano and drums at a very young age. He has played bass guitar since age 15.

In the spring of 2008, John Spiker joined the band Filter. After touring the majority of '08, they've played shows throughout the US, Canada, and Europe. They have since returned to Los Angeles to shoot a Live Concert DVD set to be released in 2009. Spiker played bass on Steve Earle's Washington Square Serenade in 2007, which won a Grammy for Best Contemporary Folk Album. He also plays with Tenacious D, and has toured with them in North America, Europe and Australia. He recently played the UK's Reading and Leeds festivals with the D in the Fall of 2008. He plays bass and sings in Kyle Gass's side project Trainwreck. Spiker also plays in the band Kidneys, fronted by Bad Religion's Brooks Wackerman, and Professional Assassins.

John spent most of 2009 in the studio playing as a session bassist on: the upcoming Filter album, Jonas Brothers tracks, Steve Earle's Townes, and Soundtracks for "The Runaways", "2012 (film)", "Stepfather" and others.

In 2010 Spiker joined a few new bands as well as doing session work both as a bassist, producer, and engineer. He recently played "Bonnaroo" with "[Tenacious D]]" and "Wango Tango" with "Justin Gaston" as well as touring with "Trainwreck". Other bands he's playing with are "Abandoned Pools", "Zac Poor", Brooks Wackerman's "Kidneys" and various up and coming acts.