"Crazy" is a song written by English singer-songwriter Seal and English songwriter Guy Sigsworth. It was produced by Trevor Horn and released by ZTT Records in November 1990 on Seal's debut album, Seal (1991). The song became his first commercial hit, reaching No. 2 in the United Kingdom, while becoming his first top ten single in the United States. It has since been covered by several artists, including Alanis Morissette, whose version was released as a single from her 2005 compilation album, The Collection.

Seal wrote "Crazy" in 1990 inspired by the fall of the Berlin Wall and the Tiananmen Square massacre in 1989. In 2015, Seal said of the song's conception in 1990: "I felt the cycle had reached its apex. I felt the world changing and I felt profound things happening."^[5]

According to the song's producer Trevor Horn, "Crazy" was made over the course of two months: "'Crazy' wasn't an easy record to make, because we were aiming high."^[6]

The song's signature is a keyboard mantra that continually swells and swirls, driven by bass-heavy beats and wah-wah pedal guitars played by Simply Red guitarist Kenji Suzuki. Its floating, ambient stylings established a sound years before The Politics of Dancing by Paul van Dyk or William Orbit's work with Madonna and All Saints. Orbit produced a remix of the track for the single release. Seal's vocals are deeply melodic and soulful, at times with a characteristic rasp, while at others soaring high above the backing track. In an interview with Q, Seal told:

I had no doubt about 'Crazy'. I always thought it was a potential No. 1—even though it never was! It's the first song I wrote on the guitar, and the first song where I said everything I wanted to say in a concise way. Before that my songs had been too long. But as soon as I wrote the hook, I knew it was a potential hit.^[7]

In the United Kingdom the song was released as the first single from the album Seal in November 1990 (see 1990 in music)^[1] and peaked at number two on the UK Singles Chart in January 1991^[8] and is Seal's biggest solo hit there.^[9] The single sold over 200,000 copies, thus earning a BPI Silver certification.^[1] It won Seal a number of awards including the 1992 Ivor Novello award for songwriting.^[10]

The single was released in the United States in 1991, debuting at number eighty-three on the Billboard Hot 100 in mid-June; it peaked at number seven in late August and remained on the chart for nineteen weeks, until October.^[11] It reached the top five on the Modern Rock Tracks chart and the top twenty on the Hot Dance Music/Maxi-Singles Sales chart.^[12][13] It was the most commercially successful single from Seal and was Seal's biggest hit in the US until "Kiss from a Rose", which reached number 1 in 1995. In August 2003 an acoustic version of "Crazy" charted at number four on Billboard's Hot Digital Tracks chart.^[14]

Larry Flick from Billboard felt that UK newcomer Seal "comes on like a cross between Terence Trent D'Arby and Lenny Kravitz on this keyboard-driven funk'n'soul jam."^[15] A reviewer from Melody Maker named it Single of the Week, complimenting it as "a lush, sumptuous all-pervading piece that's as much of a song as it is a dancetrack."^[16] Pan-European magazine Music & Media declared it as "adventurous techno-pop by this promising UK singer who sang on Adamski's recent hit single "Killer". Produced by Trevor Horn, this classy, galloping mix of funk, soul and pop is currently riding high on the UK charts. Europe should be next."^[17] Jack Barron from NME felt that the song "finds all of Seal's talents intact."^[18] Another editor, Barbara Ellen, also named it Single of the Week", adding, "The best thing about "Crazy" is the intelligent manipulation of vocals. They're eerie and penetrating anyway, but the production guy has wisely given them some space to breath and grow, at least he does at the beginning of the record."^[19] Bob Mack from Spin noted Seal's "stirring vocal that's being compared to Marvin Gaye", explaining that "based on a '70s cop-show-type bass synth line, "Crazy" flows natch enough that you hum along on first listening."^[20] Eve Zibart from The Washington Post named it "easily the best pop single of 1991", remarking that the "moody" song offers "his simple philosophy: "We're never gonna survive unless we get a little crazy"."^[21]

"Crazy" was awarded one of BMI's Pop Awards in 1993, honoring the songwriters, composers and music publishers of the song.^[22] In 1999, the Daily Vault's Jason Warburg stated that it's "an obvious club track with its propulsive synthesizer melody and driving rhythm section. The Shaft guitar part closing out the bridge is a nice touch, too, demonstrating just how effectively Seal has grafted synthesized dance music onto its funk roots."^[23] Siobhan O'Neill commented on the song in the 2010 book 10,001 Songs You Must Hear…, "Full of drug and dance scene references, "Crazy" blends soulful lyrics and husky vocals with Horn's trademark sweeping orchestration and a voguish electronic backing—a combination that, in the wake of this and Massive Attack, became the template for a whole strand of dance music."^[24]

The single's music video, directed by Big TV!, features multiple re-creations of Seal himself performing the song against a primarily white background. A female dancer appears just before the bridge of the song, and at the end Seal holds a dove while snow falls on him. The video received heavy rotation on MTV Europe.^[25]

The song is played during a party scene in the film Naked in New York (1993),^[26] is heard in a Baywatch episode, in the trailer for the film The Basketball Diaries (1995) and featured in a scene in Clockers, released in 1995. It is also heard in the middle of "True Calling", the second episode of Season 6 of TV's Cold Case. It was also used as a theme song for the ABC-TV series Murder One, which was transmitted during the 1995–1996 television season. It is also heard in the film Mystery Date. The song featured in the 1999 Robbie the Reindeer film Hooves of Fire, where it is performed by a seal.

• 7"

1. "Crazy" – 4:30
2. "Sparkle" – 3:36

• CD

1. "Crazy" – 4:30
2. "Crazy" (extended version) – 5:09
3. "Krazy" – 6:26 (producers: Trevor Horn, Tim Simenon)

• CD maxi single

1. "Crazy" (7" mix) – 4:30
2. "Crazy" (William Orbit mix) – 5:25
3. "Crazy" (acoustic version / instrumental version) – 6:57
4. "Crazy" (a cappella mix) – 3:27
5. "Sparkle" (extended version) – 6:23
6. "Krazy" – 6:27
7. "Crazy" (Do You Know the Way to L.A. mix) – 3:50
8. "Crazy" (Chick on My Tip mix) – 6:47

The hard rock band Talisman covered the song on their 1995 album Life, and a version by power metal band Iron Savior is included as a bonus track on their 2002 album, Condition Red.

Two cover versions were released in 2003: one by punk covers band Me First and the Gimme Gimmes on their 2003 album Take a Break, and another by alternative metal band Mushroomhead as a hidden track on their 2003 album, XIII. In 2004, the song was covered by Brooklyn Bounce.

Indie artist Brian Eaton covered the song on his 2011 pop/rock album, Graphic Nature.^[57]

French pop singer Tal covered this song for her debut album, Le droit de rêver, in the deluxe edition released in 2012.

In 2022, Denver Colorado-based alt-rock band Ancient Echoes released a cover version.