45

45 may refer to:

• 45 (number)
• one of the years 45 BC, AD 45, 1945, 2045

Film

• 45 (2009 film), directed by Peter Coster
• 45 (upcoming film), an upcoming Kannada-language action fantasy film
• .45 (film), directed by Gary Lennon (2006)

Music

• 45 (Jaguares album), 2008
• 45 (Kino album), 1982
• "45" (Bon Iver song), 2016
• "45" (The Gaslight Anthem song), 2012
• "45" (Shinedown song), 2003
• "45" (Elvis Costello song), 2002
• The group Stars on 45 and its self-titled 1981 song, "Stars on 45"
• "Forty Five", a song by Karma to Burn from the album Appalachian Incantation, 2010
• 45 rpm record or 45, a common form of vinyl single

In science

• The atomic number of rhodium

Astronomy

• Messier object M45, a magnitude 1.4 open cluster in the constellation Taurus, also known as the Pleiades
• The New General Catalogue object NGC 45, a magnitude 10.6 spiral galaxy in the constellation Cetus

Other uses

• Donald Trump, the 45th and 47th President of the United States, with the nickname "45"
• 45 (book), written by Bill Drummond
• .45 caliber, a family of firearm cartridges
  • A nickname for a handgun chambered in .45 caliber, such as the M1911 pistol or Colt Single Action Army
  • .45 ACP, pistol cartridge
  • .45 Colt, revolver cartridge
• Jacobite rising of 1745 or "The '45", in the United Kingdom
• Forty-fives, a card game
• 'The 45%', collective term used by Scottish independence campaigners (after ratio of support in 2014 referendum)
• Fortyfive, a software development company
• 45 Eugenia, a main-belt asteroid
• Rover 45, a small family car
• The '45 refers to the Jacobite rising of 1745 in Great Britain, or the year that World War II ended, which was 1945.
• 45, a book of essays by record producer Bill Drummond, derived both from the speed of a pop single and from his age when he finished writing it.
• In years of marriage, the sapphire wedding anniversary.
• Forty-five (audio drama), a Big Finish 2008 audio play made for the forty fifth anniversary of the British science fiction television show Doctor Who.