AAC to FLAC converter
Convert AAC to FLAC in your browser. No upload and no account: the file never leaves your device, so the only size limit is your device’s memory.
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Every request this page makes is listed as it happens. You’ll see our own code loading, and for some formats a codec engine, but never your file going out.
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Related conversions
Convert other formats to FLAC
Read more about the AAC format and the FLAC format, or see every audio tool and all audio conversions.
Should you convert AAC to FLAC?
Only when software insists on FLAC. It stores the decoded AAC perfectly, but the detail the AAC discarded is already gone, so the FLAC is bigger without sounding better.
AAC is a bare AAC audio stream without the M4A wrapper; FLAC is lossless audio at roughly half the size of WAV. Use FLAC to archive music and recordings you may want to convert again later.
| Property | AAC | FLAC |
|---|---|---|
| Compression | Lossy | Lossless |
| Typical quality | 96–256 kbps | lossless, 16 or 24-bit |
| Support | Opens almost everywhere | Opens almost everywhere |
| Best for | Recordings captured from streams and broadcast | Archiving music and recordings without losing anything |
| Introduced | 1997 | 2001 |
How to convert AAC to FLAC
- 01
Add your AAC
Drop your AAC file onto the box, or click to choose it. It is read from your disk and stays there.
- 02
Check the settings
The output is already set to FLAC. Change the bitrate if you want to; the defaults suit most files.
- 03
Save the FLAC
Press convert and save the FLAC. Several files come back together as a ZIP.
What changes when AAC becomes FLAC
Bigger, not better
FLAC can’t restore what AAC compression removed. It does make editing easier and stops further loss, which is why editors and some broadcast systems ask for it.
Expect a much larger file
FLAC is far bigger for the same content. Choose it because something needs FLAC, not to send or store the file. AAC: About 1 MB a minute at 128 kbps. FLAC: About 5–7 MB a minute for music.
This page is put together from our notes on each format, choosing only what is true of AAC and FLAC, so every pairing states the same facts the same way. How these pages are made.
Why it doesn’t upload
Recordings are often private: interviews, voice notes, unreleased music. Your browser can decode and encode audio itself, so there is no reason to send it anywhere.
How to check for yourselfWorth knowing
- About the AAC. Raw AAC has no index, so players often show the wrong duration or can’t seek; saving it as M4A fixes both.
- About the FLAC. FLAC made from an MP3 is lossless only in name: it perfectly preserves an already lossy recording, at five times the size.
- MP3, WAV, M4A, OGG, Opus and FLAC are converted by your browser directly. WMA, AMR, APE, AC3 and the other specialist formats use the FFmpeg engine, a one-time 31 MB download.
Questions
Does converting AAC to FLAC lose quality?
No quality is lost converting to FLAC, though it can’t restore what the AAC already discarded.
Will an FLAC play in my car or on my phone?
FLAC opens almost everywhere: most modern players, Android and recent iPhones; some car stereos and older apps don’t.
Read more about this
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