Isotope was a British jazz-rock band based around guitarist Gary Boyle.

Boyle founded the band in June 1972 and a first album, Isotope, was largely composed by keyboardist Brian Miller. Jeff Clyne was on bass and Nigel Morris was on drums. However, Miller and Clyne left in 1974 to be replaced by Hugh Hopper and Laurence Scott respectively. After touring, this new line-up recorded Illusion.

Further touring followed and there were various personnel changes. Deep End was recorded in 1976 with two keyboardists, Zoe Kronberger and Frank Roberts. Hopper played on one track, but the bass was otherwise handled by Dan K. Brown.

Boyle subsequently focused on a solo career.