Convert AAC files to FLAC free in your browser — no signup, no install, and the file is never uploaded to a server. FLAC keeps full quality with no further loss.
Add your AAC file
Drag the AAC file onto the drop area above, or click it to pick a file from your device. You can add several files at once.
Confirm FLAC as the output
FLAC is already selected as the output format on this page. You can pick the bitrate — higher keeps more of the sound, lower makes a smaller file.
Run the conversion
Press the convert button. Audio decodes and re-encodes in your browser — a normal song finishes in a few seconds.
Download the FLAC file
When it finishes, download the FLAC file. Converting multiple files gives you the option to download them together as a ZIP.
A lossy format designed as MP3's successor, delivering better quality at the same file size. It is the default for iTunes, YouTube, and streaming services.
A lossless format that preserves 100% of the original quality while roughly halving the size of a WAV. It is the standard among audiophiles.
Yes. AAC to FLAC conversion is completely free with no signup, no watermark, and no daily limit on the free plan for ordinary use.
No. The conversion runs entirely inside your browser using WebAssembly, so the AAC file never leaves your device. That is also why it works without an internet connection once the page has loaded.
The free plan handles files up to 200MB. Because processing happens on your own device, very large files depend on your computer's memory rather than a server quota.
Audio converter
What each file format is, what it is used for, and which formats it can be converted to.
Open converter Browse the full format reference