In 1985, Heaton formed a guitar band called the Housemartins. Their bassist left on the eve of their first national tour, so Cook agreed to move to Hull to join them. The band soon had a hit single, “Happy Hour”, and their two albums, London 0 Hull 4 and The People Who Grinned Themselves to Death, peaked in the Top 10 of the UK Albums Chart. They also reached number one just before Christmas 1986 with a version of “Caravan of Love”, originally a hit the year before for Isley-Jasper-Isley. By 1988 they split up. Heaton and the band’s drummer Dave Hemingway went on to form The Beautiful South, while Cook moved back to Brighton to pursue his interest in the style of music he preferred. He started working with young studio engineer Simon Thornton, with whom he continues to make records. All of Cook’s records since have involved both of them to varying degrees (Thornton is credited in 2004 as “Executive Producer”, for example).

Cook achieved his first solo hit in 1989, “Blame It on the Bassline”, featuring future Beats International member MC Wildski. Credited to “Norman Cook feat. MC Wildski”, the song followed the basic template of what would become Beats International’s style. It was a modest hit on the UK Singles Chart, reaching number 29.

Cook then formed Freak Power with horn player Ashley Slater and singer Jesse Graham. They released their debut album Drive-Thru Booty in 1994, which contained the single “Turn On, Tune In, Cop Out”. Levi’s used the song in a multimillion-dollar advertising campaign. In 1996, Cook rejoined Freak Power for their second album, More of Everything for Everybody.

Cook adopted the pseudonym Fatboy Slim in 1996. Cook said of the name: “It doesn’t mean anything. I’ve told so many different lies over the years about it I can’t actually remember the truth. It’s just an oxymoron—a word that can’t exist. It kind of suits me—it’s kind of goofy and ironic.”

The Fatboy Slim album and Cook’s second solo album, Better Living Through Chemistry (released on Skint Records in the UK and Astralwerks in the US), contained the Top 40 UK hit “Everybody Needs a 303”. Fatboy Slim’s next work was the single “The Rockafeller Skank”, released before the album You’ve Come a Long Way, Baby, both of which were released in 1998. “Praise You”, also from this album, was Cook’s first UK solo number one. Its music video, starring Spike Jonze, won numerous awards. On 9 September 1999, he performed “Praise You” at the 1999 MTV Video Music Awards in New York City, and won three awards, including the award for Breakthrough Video.

He married TV personality Zoe Ball in 1999 at Babington House in Somerset. In January 2003, Cook broke up with Ball, but three months later they reconciled. They have a son, Woody Fred Cook (born 15 December 2000), who appeared on the Channel 4 show The Circle in 2019, and a daughter Nelly May Lois (born 14 January 2010), who premiered a DJ set as Fat Girl Slim with Camp Bestival during the COVID-19 pandemic to raise money for the Ellen MacArthur Cancer Trust and The Trussell Trust. They live in Western Esplanade, Hove. On 24 September 2016, Cook and Ball announced their separation after 18 years.

In 2000, Fatboy Slim released his third studio album, Halfway Between the Gutter and the Stars, and featured two collaborations with Macy Gray and “Weapon of Choice”, which also was made into an award-winning music video, starring Christopher Walken. The album also included “Sunset (Bird of Prey),” whose socially significant video sampled the 1964 “Daisy Girl” campaign ad. At the 2001 MTV Video Music Awards in New York, Fatboy Slim won six awards for “Weapon of Choice”, the most awards at the ceremony.

On 13 July 2002, Fatboy Slim performed the second of his free open-air concerts on Brighton beach. Although organisers expected a crowd of around 60,000 people, the event instead attracted an estimated 250,000 who crammed the promenade and beach between Brighton’s piers. Local police forced the event to end early amid safety concerns, overcrowding, and one death.

In 2003, he produced “Crazy Beat” and “Gene by Gene” from the Blur album Think Tank, and in 2004, Palookaville was Cook’s first studio album for four years.

In June 2005, Fatboy Slim filled the Friday night headline slot on the “Other Stage” at the Glastonbury Festival. In 2006, Fatboy Slim filled the Saturday headline slot at the Global Gathering festival at Long Marston Airfield in the English Midlands. He played a two-hour set, appearing in front of a visual stage set comprising video screens and 3D lighting. A firework display rounded off the show. Having been banned by police from playing in Brighton since 2002, Fatboy Slim was given permission in 2006 to play again in his home town. On 1 January 2007, he played to an audience of more than 20,000 fans along Brighton’s seafront. Tickets to the event, titled “Fatboy Slim’s Big Beach Boutique 3”, were made available only to individuals with a BN postcode. The concert was deemed a stunning success by Sussex police, Fatboy Slim, and the crowd. The Cuban Brothers and David Guetta opened the concert. The next similar event, ‘Big Beach Boutique 4’, was held on 27 September 2008.

Fatboy Slim’s greatest hits album, Why Try Harder, was released on 19 June 2006. It comprises 18 tracks, including ten Top 40 singles, a couple of Number Ones and two new tracks, “Champion Sound” and “That Old Pair of Jeans”.

In 2006, Cook travelled to Cuba, and wrote and produced two original Cuban crossover tracks for the album The Revolution Presents: Revolution, which was released by Studio ! K7 and Rapster Records in 2009. The tracks are “Shelter” (which featured longtime collaborator Lateef) and “Siente Mi Ritmo”, featuring Cuba’s female vocal group Sexto Sentido. The recordings took place at Cuba’s EGREM Studios, home of the Buena Vista Social Club, and featured a band of young Cuban musicians, including Harold Lopez Nussa. Another track recorded during these sessions, “Guaguanco”, was released separately under the Mighty Dub Katz moniker in 2006.

The Brighton Port Authority debuted in 2008 with a collaboration with David Byrne and Dizzee Rascal titled “Toe Jam”, along with a video featuring nude dancers with censor bars on them, making pictures and words with them.

Cook has been responsible for successful remixes for Cornershop, Beastie Boys, A Tribe Called Quest, and Wildchild. In 2008, he did a remix of the track “Amazonas” for the charity Bottletop.

In 2008, Fatboy Slim played at the Glastonbury Festival again and headlined the O2 Wireless Festival and Rockness Festival. According to an NME interview, this may have been one of the last times he performed as Fatboy Slim, as he may now be focusing on his new band, The Brighton Port Authority (BPA). Also in 2008, Fatboy Slim closed out the famed “Sahara” tent on Friday of the Coachella Valley Music Festival. His introduction included a Charlie and the Chocolate Factory opening, that has been called by many one of the most memorable Sahara performances ever.

It was reported in 2008 that he held the Guinness World Record for the most Top 40 hits under different names. The following is a list of lesser-known aliases used by Cook in performances.

In 2009, he toured Australia in the Good Vibrations Festival. Also in 2009, he played in Marlay Park, Dublin alongside David Guetta, Dizzee Rascal, and Calvin Harris, as well as one huge performance at the Sziget Festival in Budapest. He also performed at V Festival 2009.

At Glastonbury 2009, he played an unadvertised concert in the “pinball-machine” stage at trash city.

On 4 March 2009, Cook checked into a rehabilitation centre in Bournemouth to fight alcoholism. Due to an extended stay in the rehabilitation centre, his performance at Snowbombing, a week-long winter sports and music festival held in the Austrian ski resort of Mayrhofen, was cancelled, with the slot being filled by 2ManyDJs. Cook left the clinic at the end of March. As of 4 March 2019 he has not used drugs or alcohol for 10 years.

In 2010 Cook released a mix album, The Legend Returns, as a covermount album in the June 2010 issue of Mixmag. He returned as Fatboy Slim when performing at Ultra Music Festival in Miami in March 2012.

In 2010, Fatboy Slim headlined the east dance at Glastonbury Festival. On 18 June 2010, he performed in Cape Town, South Africa as part of the Cool Britannia FIFA World Cup music festival at the Cape Town International Convention Centre. He also performed in Napoli on 15 July, at Neapolis Festival. On 30 May 2011, he performed as the headliner for Detroit’s Movement Electronic Music Festival in Detroit, Michigan, USA. On 25 September 2011, Fatboy Slim headlined the Terrace at Ibiza’s famed Space nightclub’s We Love Sundays closing party. On 29 October 2011, Fatboy Slim opened at the San Francisco Bill Graham Civic Auditorium, following up on the 30th, closing out the Red Bulletin/Le PLUR Stage at the Voodoo Music Experience in New Orleans, Louisiana. On Saturday, 24 March 2012, Fatboy Slim performed a live DJ set on the main stage at Ultra Music Festival in Miami, Florida. In addition to his other 2011 performances, Fatboy Slim also played a headline gig at the Bestival in the Isle of Wight on 11 September.

Cook produced the single “Mama Do the Hump” by fellow Brighton band Rizzle Kicks released in December 2011 which peaked at number 2 in the charts.

On 12 August 2012 he performed Rockefeller Skank and Right Here, Right Now at the 2012 Summer Olympics Closing Ceremony, and on 1 September Cook performed at Brighton Pride.

In March 2012, Cook hosted a one-hour radio programme, titled On The Road To Big Beach Bootique 5, on XFM. It consisted of 10 shows.

On 20 June 2013, Cook released his first charting Fatboy Slim single in seven years; “Eat, Sleep, Rave, Repeat” with Riva Starr and Beardyman. Supported by a remix from Scottish DJ Calvin Harris, the song topped the UK Dance Chart that year.

In 2013, Fatboy Slim played at Ultra Music Festival, Wavefront Music Festival, Exit Festival, Bestival, and Glastonbury Festival (as a special guest on the Wow! and Arcadia stages).

On 6 March 2013, Fatboy Slim played at the House of Commons in Westminster, London. This was the first time that a DJ had ever performed there, and was in aid of the Last Night A DJ Saved My Life Foundation, which is aimed at encouraging 16- to 25-year-olds to get more involved in their communities through grassroot initiatives and to raise awareness for community music projects.

In May 2014, Fatboy Slim played Coachella for a second time and again on the Sahara stage. This time he did not close the tent. In Essex at the We Are FSTVL and was the biggest act on the bill, playing for nearly two hours.

In December 2014, Fatboy Slim played 3 sold-out shows including The Warehouse Project in Manchester & O2 Brixton Academy, with supporting acts such as VAS LEON with Arthur Baker for Slam Dunk’d, and DJ Fresh.

In 2015, Cook released a 15th anniversary edition of Halfway Between the Gutter and the Stars. This was supported with the release of miscellaneous remixes. In May 2015, Cook compiled The Fatboy Slim Collection, an album of songs used throughout his sets over the years.

On 15 May 2016 he played a private two-hour set “Baby Loves Disco” for pre-school children and their parents during the festival Brighton Fringe holding

At Glastonbury 2016, he played the John Peel stage for the first time.

In 2017, Fatboy Slim returned with his single “Where U Iz”, released on 3 March that year. Later that year, he released another collaboration with Beardyman titled “Boom F**king Boom”.

In 2018, a remix album from Australian artists of Cook’s previous works was released, titled Fatboy Slim vs. Australia.

In October 2019, Cook performed a mashup of his track “Right Here, Right Now” and Greta Thunberg’s United Nations speech during a concert in Gateshead, England.