Tom Holkenborg (born 8 December 1967), better known as Junkie XL or occasionally JXL, is a Dutch multi-instrumentalist, composer, producer, and engineer. He uses the name JXL in cases where the term "Junkie" might cause offense. Holkenborg says of his name: "I called myself Junkie XL from the point of view that once you're completely overworked, you never want to go there again. The 'XL' stands for expanding limits; broadening up your vision."

Originally known for his trance productions, he has moved to producing electronica and big beat music and film scores in recent years. Junkie XL is probably best known for his remix of Elvis Presley's "A Little Less Conversation", which became a worldwide hit in 2002.

Holkenborg was born in Lichtenvoorde, Gelderland, Netherlands. Classically trained by his mother – herself an accredited music teacher – Holkenborg started playing piano when he was four years old, drums when he was eight, and guitar at 12. Already influenced by the psychedelic-pop of Pink Floyd and King Crimson, he took up the bass by age 14. After taking a job at a local music store selling keyboards and other digital gear, he began to have an appreciation for the combination of electronic and organic sounds. It was shortly after he discovered synthesizers that he joined the Dutch New Wave ensemble Weekend at Waikiki as a multi-instrumentalist and producer, touring extensively with the band, including through parts of the former Soviet Union, from 1988 to 1991. He also contributed to their final album, Sputnik. In 1993, Holkenborg produced Almost a Dance by Dutch metal band The Gathering, and later that year went on to form the industrial rock band Nerve with Phil Mills. After signing with influential label Play It Again Sam in 1992 and releasing two LPs – Cancer of Choice (1993) and Blood & Gold (1994) – he continued as a producer-for-hire, working with hardcore and metal bands like Sepultura, Fear Factory, and Dog Eat Dog while simultaneously licensing some of his instrumental electronic tracks for racing video games like The Need For Speed and Test Drive 5. It was during this time that he also began scoring the Dutch feature film, Siberia, which would be released by Warner Brothers Netherlands.