AVR may refer to:
- Avon Valley Railway, a heritage railway in the United Kingdom
- Atmel AVR, a family of microcontrollers
- Assiniboine Valley Railway, a minimum gauge railway in Winnipeg, Canada
- Allegheny Valley Railroad, shortline railroad in Pennsylvania, U.S.
- Audio/video receiver
- Aortic valve replacement
- Automatic voltage regulator
- Video file used by certain set-top boxes which use MPEG transport stream (TS) as video codec
- AVR reactor, a German prototype pebble bed reactor
- Annapolis Valley Radio, a country station located in Kentville, Nova Scotia
- Aboriginal Voices Radio, an Aboriginal Canadian national radio network
- Armed violence reduction
- Avacyn Restored
- AVR -Aaudio Video River
aVR may refer to:
- Lead augmented vector right (aVR), a voltage difference in electrocardiography