X2

X2 may refer to:

Mathematics

Square (algebra), also known as the "algebraic square", a concept in algebra
Chi-squared distribution, a theoretical probability distribution widely used in inferential statistics

X2 (video game), a 1997 video game
Final Fantasy X-2, a 2003 role-playing video game
Mega Man X2, a 1994 platform game
X2: The Threat, a 2003 space simulation game
Dance Dance Revolution X2, a 2010 upcoming music video game for the PlayStation 2 by Konami
X2, the main character in Star Wars Battlefront: Elite Squadron

X2 (New York City bus)
X2, a Metrobus route
Bell X-2, an experimental supersonic aircraft
North Wing Sport X2, an American ultralight trike design
Sikorsky X2, a prototype, coaxial high-speed helicopter
SpaceShipOne flight 17P, also known as "X2", the second Ansari X Prize flight
Skycycle X-2, a rocket used by Evel Knievel
HMS X2, a Royal Navy submarine
Bathyscaphe Trieste II, also known as X-2, the US Navy bathyscaphe based on the Trieste
SJ X2, used for the X2000 train system in Sweden
Kawasaki X2, a personal water craft
X-2 Dragonfly, the company designation of the Rotor-Craft XR-11 experimental helicopter of the late 1940s
X-2 Rocket, the spacecraft used in Mission: Space in Epcot

X2 (roller coaster), a Roller Coaster at Six Flags Magic Mountain
Sendo X2, a Series 60 mobile phone
The counterintelligence branch of the Office of Strategic Services, an American agency during World War II
X-2, a hydrofoil owned by the Venture family on The Venture Bros.
a keyboard synthesizer sold by Korg in the 1990s
X2 is a transport interface used to connect enodeBs together in a LTE/4G network
X2 is also a fictional character created by renowned Pakistani writer Ibn-e-Safi in Imran Series