Convert images, documents, video and audio in your browser. Your files stay on your device.
Convert OPUS audio to FLAC, choosing bitrate, channels and sample rate. You can also trim the track or adjust its volume.
Drag one or more OPUS files onto the dashed area, or tap it to pick them from your device.
FLAC is already selected: you can adjust bitrate, channels and volume, and trim the track.
Press “Convert to FLAC”. When it’s done, download the files one by one or all together in a ZIP archive.
Good to know. Converting a compressed file to a lossless format won’t bring back lost quality, but it avoids further losses when you edit it later.
Source format
Opus Interactive Audio Codec
The most efficient audio codec available today: it’s the one behind WhatsApp voice messages and video calls. At 64 kbps speech is crystal clear and music surprisingly good.
Target format
Free Lossless Audio Codec
It compresses audio without losing a single bit: the sound is identical to the original, but the file weighs about half as much as a WAV. It’s the favourite format for archiving CDs and high-resolution music.
Audio and video use WebCodecs: they work in up-to-date Chrome, Edge, Opera and Samsung Internet, in Firefox 130+ and Safari 17+ (with a few limits on the formats they can create). If your browser can’t create the chosen format, we tell you before you start.
No. The conversion from OPUS to FLAC happens entirely in your browser, using your device’s computing power. Files aren’t sent or stored anywhere: when you close the page they’re gone from memory too.
Up to 100 files at a time. There’s no fixed size limit: it depends on your device’s memory. On smartphones it’s best to work in smaller batches with heavy files such as videos.
Yes, with up-to-date Safari, Chrome, Firefox, Edge and Samsung Internet. On phones, converted files end up in the Downloads folder or the Files app.
Only to open the page (and, the first time, to download the components needed for that type of file). After that the conversion keeps working even if the connection drops.