Vast or VAST may refer to:

• Vast (novel), a 1998 science fiction novel by Linda Nagata
• Vast (2011 film), a Dutch film, winner of the 2011 Golden Calf for Best Television Drama
• Vast Broadband, an American cable and internet company
• Vast Studios, a Canadian video game developer
• Fernand Vast (1886 - 1968), French cyclist
• Vast (company), an American aerospace company
• FC Vast Mykolaiv, Ukrainian football team from the city of Mykolaiv.

• VAST, an American alternative rock band
• Variable Architecture Synthesis Technology, a digital sound synthesis method for the Kurzweil K2000
• Video Ad Serving Template, a metadata format for video advertising
• Vidya Academy of Science and Technology, in Thrissur, Kerala, India
• Vietnam Academy of Science and Technology, in Hanoi
• Viewer Access Satellite Television, a satellite TV service provided by the Australian government
• Visual Analytics Science and Technology
• Voest-Alpine Services and Technologies, a unit of Siemens headquartered near Pittsburgh, Pennsylvania