A device is usually a constructed tool. Device may also refer to:

• Appliance, a device for a particular task
• Computer, a computing device
• Device file, an interface of a peripheral device driver
• Electronic component, a device that can be embedded in the construction of electronic hardware
• Gadget, generally synonymous with device; often used when a more specific word is not well-known or cannot be recalled
• Handheld device, a small computer such as a phone or tablet
• Machine, a mechanical device
• Medical device, a device intended for medical use
• Peripheral device, hardware that is external but accessible to a computer

• Improvised explosive device (IED)
• Nuclear weapon

• Device (metal band), American industrial metal band active 2012–2014
• Device (pop-rock band), American pop-rock trio from the mid 1980s

• Device (Device album), 2013
• Device (Eon album), 2006

• Plot device, as in storytelling
• Rhetorical device, a technique used in writing or speaking
• The Device, a 2014 American science fiction horror film

• Dev1ce or Device, nicknames for Nicolai Reedtz, a Danish professional Counter-Strike player
• Device, something that can be trademarked, such as a logotype (or "logo") in printing or in law
• Devices, aspects of a military-award decoration in the United Kingdom
• Personal device, another name for a heraldic badge

• Alizon Device (died 1612), executed as one of the Pendle witches
• Elizabeth Device (died 1612), executed as one of the Pendle witches
• James Device (died 1612), executed as one of the Pendle witches
• Jennet Device (fl. 1612), witness at the trial of the Pendle witches

• Devise