4D or 4-D primarily refers to:
Four-dimensional space 4-dimensional spacetime: three-dimensional space of length, width, and height, plus time
It may also refer to:
Computers and photography 4D (software), a complete programming environment including database and web server 4D SAS, developers of 4D and Wakanda 4D Inc, a US-based subsidiary of 4D SAS 4D BIM, a term used in computer aided design 4D printing Cinema 4D, a commercial cross platform 3D graphics application SGI IRIS 4D, a line of workstations from Silicon Graphics 4D, a photo print size for digital cameras
Arts and entertainment 4D (album), a 2010 album by Matthew Shipp "4-D" (The X-Files), an episode of The X-Files 4D Audio Recording system, an audio recording system developed by Deutsche Grammophon 4D film, a high technology film experience augmented with physical or environmental effects 4DTV, a satellite TV broadcasting technology from Motorola 4DX, a 4D film format "4D", a song by Grand Mixer DXT and Bill Laswell from Aftermathematics (2003) "4D", a song by Northlane from Alien (2019) 4D, the production code for the 1975 Doctor Who serial Revenge of the Cybermen
Other Class 4-D, a classification of the Selective Service System 4-D (psychedelic), a psychedelic drug 4D (train) in Melbourne, Australia 4-Digits, a lottery in Malaysia and Singapore Air Sinai (IATA: 4D) Ring finger, the fourth digit (abbreviated 4D) of the hand Potez 4D, a four-cylinder aircraft engine
See also D4 (disambiguation) DDDD (disambiguation) Fourth dimension (disambiguation) Four Dimensions (disambiguation)