Step 1: Deliver your AAC files using the button above or by place and set.
Step 2: Click the 'Process' button to start the processing.
Step 3: Obtain your converted FLAC files.
AAC to FLAC Processing FAQ
What bitrate does the FLAC file use?
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A lossy FLAC is encoded at 192 kbps by default. The Audio Quality setting also offers 320 kbps for the best quality and 128 kbps for a smaller file. A lossless FLAC (WAV, FLAC) ignores the bitrate and keeps every sample.
Will going from AAC to FLAC reduce my audio quality?
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If AAC is lossy and FLAC is lossless (e.g. MP3 → WAV), the FLAC file is no better than the AAC source — you cannot recover information that was thrown away by the original lossy encode. If AAC is lossless and FLAC is lossy, expect the FLAC codec to recompress; at 192 kbps this is transparent for nearly all material.
Can I batch convert hundreds of AAC files to FLAC?
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Several files in one job need a paid plan. Free use is one file per conversion, one conversion an hour. On a paid plan you can add several files to one job, then download each result on its own or all of them in one ZIP.
Can I normalize loudness in the AAC to FLAC step?
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Not in this step. The converter has no loudness setting and leaves the level as it is. To even out the volume, run the finished FLAC through a Normalize tool on this site.
Will the FLAC play on my car stereo, iPod, or Sonos?
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MP3 plays almost everywhere. AAC plays on Apple devices, most Android phones and Sonos. FLAC plays on Sonos and Android but not on older iPods, and WAV plays on nearly everything but makes large files. There are no device presets on this page, so choose the target format your player supports.
Is my AAC file private during conversion?
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Yes. Uploaded AAC files are processed on our own conversion servers, no person reviews them, and they are never shared. The upload and the converted FLAC are both deleted automatically about 24 hours after the conversion, which leaves time to download the result. See /privacy/ for the full policy.
How long does converting a 1-hour AAC to FLAC take?
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It depends on the size and length of the file. Small documents and images are usually ready quickly. Long videos take the longest, because most video conversions re-encode every frame.
Why is the FLAC file louder or quieter than the AAC source?
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The converter does not change the level: it has no gain or normalize setting. If you hear a difference, your player or media library is probably applying ReplayGain or its own volume levelling on playback; switch that off to hear the FLAC as it is.
Can I convert AAC streaming downloads to FLAC?
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If the AAC download is unprotected (no DRM), yes. DRM-encrypted streaming files (Spotify offline, Apple Music) are encrypted at the byte level and we cannot decrypt or process them. Sources from Bandcamp, SoundCloud, archive.org, and personal recordings convert without issue.
