Upload a OGG file and get a FLAC back. No signup, no watermark, no limit on how many.
OGG here means Vorbis audio in an Ogg container — a patent-free lossy codec that generally beats MP3 at the same bitrate.
Where you run into it: Game audio, Wikipedia and Wikimedia files, Spotify's streaming internals, Linux desktops.
What it costs you: Technical merit never bought it consumer support: plenty of car stereos and older phones simply do not list it.
FLAC compresses losslessly: it typically halves a WAV and gives back bit-for-bit the same audio when decoded. It is free, open, and widely supported outside Apple's world.
Where you run into it: Archived rips, Bandcamp and Qobuz downloads, anyone who keeps a music library they intend to still have in ten years.
What it costs you: Half of enormous is still large, and some hardware — car head units especially — will not touch it.
The audio is decoded from Vorbis — or from Opus, since .ogg names a container and carries either — and compressed again losslessly, which preserves it exactly as it is rather than as it once was. The two formats are relatives: FLAC came out of the same organisation as Vorbis, uses the same tagging system, and can even be carried inside an Ogg container itself. That shared ancestry helps less than you would expect, which is the one practical thing to know before you start.
Here is where the shared ancestry lets you down. An Ogg keeps its artist, title and date in Vorbis comments attached to the audio stream rather than to the file as a whole, and those do not come through this conversion — where an MP3's or an M4A's tags do. Expect to retype the metadata afterwards, which is worth planning for if you are working through a batch from Wikimedia Commons or a game archive: note what each file was before you convert, because afterwards the FLAC will not be able to tell you.
Yes, entirely, and there is no cap on how many files you convert. No account, no watermark, no trial.
Nothing further is lost and nothing is repaired. Two details belong to this source in particular. Vorbis writes no padding at the edges of a file, so the FLAC begins on the same sample the Ogg did — which matters if the file is a loop or part of a timed sequence. And if your .ogg turns out to hold Opus, the decode always arrives at 48 kHz whatever it was recorded at, so the FLAC will be a 48 kHz file regardless of what went in.
Five to eight times a music Ogg, though speech behaves quite differently: a mono voice recording compresses far better than music, often to around 40 percent of its uncompressed size where an album manages 50 to 60. So a voice note grows by a startling ratio and still lands at only a few megabytes, while a three-minute track goes from 4 MB to something over 25.
Yes — FLAC is one of the formats this converter writes, so the reverse page exists at /flac-to-ogg/. The trip out is exact, because FLAC discards nothing — it is the return to OGG that re-encodes. A round trip therefore costs one more generation rather than two, and the FLAC in the middle was never an improvement on the OGG you started with.
The file is uploaded to do the conversion — nothing here runs in your browser — and both your upload and the converted result are deleted the moment the file is sent back. Nothing is stored and nothing is logged beyond the request itself.