Born in 1954 in Los Angeles, California, Paich grew up with his sister in a creative family, the son of jazz pianist, composer, and arranger Marty Paich and his wife Lorraine Paich. His father introduced him to piano at age eight and he continued to study privately throughout school with noted L.A. piano teacher Sheldon Steinberg. After high school, he attended University of Southern California as a music major and further his private studies under George Tremblay. After college, Paich launched a fruitful session and songwriting career. He and his father took home a 1974 Emmy Award for Best Song or Theme for their composition "Light The Way," from the Ironside episode "Once More For Joey." He also won his first Grammy Award for co-writing Boz Scaggs' 1976 hit "Lowdown."
In 1977, Paich co-founded the rock band Toto, along with childhood friends drummer Jeff Porcaro, guitarist Steve Lukather, and Porcaro's brothers keyboardist Steve and bassist Mike. The group scored a top 5 hit with "Hold the Line" off their eponymous 1978 debut and reached the top 50 of the Billboard 200 with 1979's Hydra and 1981's Turn Back. However, it was with their fourth album, 1982's Toto IV, that they garnered global fame, topping the Billboard Hot 100 with the single "Africa" and reaching number two with "Rosanna." The album, which hit number 4 on the Billboard 200, also took home five Grammy Awards, including Album of the Year. With Toto, Paich enjoyed further success, appearing on all 14 of the group's original studio-albums. They also supplied the soundtrack for director David Lynch's 1983 film adaptaion of Dune. In 2009, he and the other members of Toto were inducted into the Musicians Hall of Fame.
Away from Toto, Paich also took on more session, production, and songwriting work. He produced Aretha Franklin's chart-topping 1977 R&B hit "Break It to Me Gently." A longtime friend of Quincy Jones and David Foster, he contributed to Michael Jackson's Thriller. In 1989, produced and arranged Patti Austin's Oscar-nominated song "The Girl Who Used to Be Me", written by Marvin Hamlisch and Alan and Marilyn Bergman for the film Shirley Valentine. As either a songwriter, arranger, and/or instrumentalist, he has contributed to projects by a bevy of performers, including Cher, Rod Stewart, Seals Crofts, The Jacksons, Steely Dan, George Benson, Glen Campbell, the Doobie Brothers, Jon Anderson, Chicago, Elton John, Sarah Vaughan, Randy Newman, P!nk, and many more.
While Toto formally ended their run following a 2019 tour, guitarist Lukather relaunched a version of the band in 2020 with Paich remaining a legacy member and occasional live guest. In 2022, Paich made his solo debut with Forgotten Toys. Produced by Joseph Williams, the album featured the single "Spirit of the Moonrise" and included guest contributions by Williams, Lukather, Brian Eno, Michael McDonald, Ray Parker, Jr., Don Felder, and Steve Jordan. ~ Matt Collar, Rovi