Opus may refer to:

• Opus (comic strip)
  • Opus the Penguin, title character of the strip
• Opus (manga), a manga by Satoshi Kon
• Opus (University of Newcastle magazine), student newspaper of the University of Newcastle, Australia
• Opus (classical record magazine), an American magazine

Opus is a lossy audio coding format developed by Xiph and standardized by the IETF, designed to efficiently code speech and general audio in a single format, while remaining low-latency enough for real-time interactive communication and low-complexity enough for low end ARM3 processors. Opus replaces both Vorbis and Speex, and several blind listening tests have ranked it higher quality than any other standard audio format at any given bitrate, including MP3, AAC, and HE-AAC.