audio/opus

The codec that won real-time audio — Opus scales from narrowband speech to full-band music and underpins WebRTC — but this type is narrower than its fame: it is registered for RTP transport only. An Opus file on disk is Ogg-encapsulated and should be served as audio/ogg with codecs=opus, not as audio/opus, however tempting the symmetry. There is no signature here because an RTP payload has no file header; the OpusHead marker lives inside an Ogg page at no fixed byte offset.

mime-db lists no extensions for audio/opus — .opus files belong to audio/ogg per RFC 7845.

Defined by RFC 7587 · IANA registration. Registry facts from the IANA media-types registry via mime-db.