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Local processing has no fixed file-size limit and depends on browser memory. Server limits: video 100 MB, other files 10 MB · Up to 5 files per batch
No registration · Free to useWhen to use this tool
AAC uses lossy audio compression for compact playback files. FLAC uses lossless compression for audio libraries and archiving.
Quality and output
FLAC and ALAC are lossless codecs. Audio can be preserved when sample rate, channels and bit depth remain compatible; check the output properties rather than assuming every source configuration is unchanged. Quality changes depend on the input and output formats. A format change cannot restore information already lost.
How to use
- Upload a valid AAC file.
- Run the conversion to FLAC.
- Download the result and check it before replacing your original.
Before you download
Compare track duration and audio properties after conversion. Album artwork, chapter markers and every metadata tag are not guaranteed to survive a format change.