AAC to FLAC Converter
Convert AAC to FLAC locally in your browser, powered by Mediabunny and native WebCodecs — nothing is ever uploaded. Drop a AAC file below to get started.
Drop files, or click to browse
AAC files only — processed one at a time
Frequently asked questions
Is this AAC to FLAC converter free?+
Yes, with no watermark, no account, and no daily limit.
Is my audio file uploaded anywhere?+
No — conversion runs locally using your browser's own built-in media codecs, entirely inside your browser tab.
Will I lose audio quality?+
Converting between compressed formats can lose a small amount of quality; converting to a lossless format like WAV or FLAC won't.
Is there a maximum file size?+
There's no fixed file-size limit since nothing is uploaded to a server. Processing time scales with the track's length rather than a hard cutoff.
How do I convert AAC to FLAC?+
Drop your AAC file into the box above — it's decoded and re-encoded as FLAC automatically, with a download ready in seconds.
About AAC and FLAC
What is AAC?
AAC is the compressed audio format behind iTunes, YouTube, and most streaming services — generally more efficient than MP3 at the same bitrate.
Full AAC format guide →What is FLAC?
FLAC is a lossless compressed audio format — same audio quality as WAV, but roughly half the file size thanks to genuine (not perceptual) compression.
Full FLAC format guide →The short version: FLAC gives you bit-perfect, lossless audio, which helps once you run into AAC's biggest limitation: slightly less universal hardware support than MP3, though still very broad. It's a natural move when your audio is headed toward archiving music at full quality.
How it works
- 1
Drop your file in
Drag your audio onto the box above, or click it to browse — there's no account to create and no upload to wait on.
- 2
Pick your settings
The output format is already set for this page — just adjust any extra options shown, if there are any.
- 3
Download the result
Your browser processes everything locally and hands you a download link the moment it's done — nothing was ever sent to a server.
Is it private?
Everything happens locally, inside this browser tab. Your audio is read from disk, processed with WebAssembly running on your own device, and handed back to you as a download — it's never transmitted anywhere, so there's nothing to intercept and nothing stored on a server.
Common use cases
- Archiving music at full quality
- Audiophile listening
- Prepping a podcast episode for a hosting platform
- Fitting a voice memo under a messaging app's size limit
Supported formats
This is one of many pairings the audio toolkit handles. In total it covers:
Related conversions
Format details
About AAC files+
AAC is the compressed audio format behind iTunes, YouTube, and most streaming services — generally more efficient than MP3 at the same bitrate.
AAC (Advanced Audio Coding) was developed as the designated successor to MP3 under the MPEG standard, using newer compression techniques to squeeze out noticeably better sound quality at the same bitrate, or an equivalent quality at a smaller file size. Apple adopted it as the default format across iTunes and the iPhone early on, and it's since become the standard codec behind most video and streaming platforms as well, since it handles the low bitrates needed for streaming particularly well.
How to open a AAC file
Opens readily in Any modern media player, Any web browser, iTunes/Apple Music. For real editing, use Audacity (free), Adobe Audition.
Good for
- better quality-per-kilobit than MP3
- the default format across Apple's ecosystem
Watch out for
- slightly less universal hardware support than MP3, though still very broad
About FLAC files+
FLAC is a lossless compressed audio format — same audio quality as WAV, but roughly half the file size thanks to genuine (not perceptual) compression.
FLAC (Free Lossless Audio Codec) was built by the Xiph.Org Foundation to solve a specific problem: WAV files are lossless but enormous, while MP3 and AAC are small but throw away audio data permanently. FLAC compresses audio the way a ZIP file compresses text — genuinely, reversibly, with zero data loss — typically landing at 50–60% of the original WAV size. That makes it the go-to format for anyone archiving music at full fidelity, at the cost of files still noticeably larger than a lossy MP3 or AAC.
How to open a FLAC file
Opens readily in VLC Media Player, Most modern phones and media players. For real editing, use Audacity (free).
Good for
- bit-perfect, lossless audio
- smaller than WAV for the same quality
Watch out for
- not supported by every device, though support is broad among dedicated audio players
Need a different format? Try the full Audio Converter, or explore all audio tools.