An open container, almost always holding Vorbis audio. Vorbis was genuinely better than MP3 and lost anyway - it's still the format of choice inside games and on Wikipedia, and still the one your car won't play.

Every conversion below runs in this page, on your own machine. Nothing is uploaded, there is no queue, and there is no account to make. Pick a target format, or just drop an OGG file above and choose afterwards.