AAC to FLAC Converter

Convert AAC to FLAC online for free. AAC to FLAC in seconds — no software install, no watermark, secure and fast.

Drag & drop your AAC file here, or

How to convert AAC to FLAC in 3 steps

  1. 1

    Upload your AAC file

    Drag and drop or select the AAC file you want to convert.

  2. 2

    Choose FLAC as output

    The output format is pre-selected for you — just confirm and start the conversion.

  3. 3

    Download your file

    Once processing finishes, download your converted FLAC file instantly.

Benefits of converting AAC to FLAC

Get lossless compression that preserves full audio fidelity at roughly half the size of WAV

Switching from AAC to FLAC means your file now offers lossless compression that preserves full audio fidelity at roughly half the size of WAV.

Wider compatibility

AAC is great for better compression efficiency than MP3 at the same bitrate, but not every app or device handles it well. Converting to FLAC sidesteps that, so the file opens wherever you need it to.

No quality compromise

ConvertFastHub runs FFmpeg at production settings, preserving as much of the original AAC fidelity as the FLAC format allows.

Keep your original too

Converting doesn't touch your source file — you get a brand-new FLAC file back and can keep both versions.

Frequently asked questions

How do I convert AAC to FLAC online?
Upload your AAC file above, select FLAC as the output format, and click Convert. ConvertFastHub processes the file in the cloud and gives you a download link — no software installation required.
Is it free to convert AAC to FLAC?
Yes. Free accounts get 10 conversions every 24 hours with files up to 50MB. For unlimited conversions, larger files up to 1.5GB, and priority processing, upgrade to ConvertFastHub Pro.
What's the advantage of FLAC over AAC?
FLAC offers lossless compression that preserves full audio fidelity at roughly half the size of WAV. Meanwhile, AAC is known for better compression efficiency than MP3 at the same bitrate — the right choice depends on where you plan to use the file.
Will converting AAC to FLAC reduce quality?
ConvertFastHub uses production-grade engines (FFmpeg, LibreOffice, ImageMagick) configured for maximum fidelity. Some format conversions are inherently lossy by design; where possible, we preserve the original quality.
Is my file safe when I convert it?
Files are uploaded over an encrypted connection directly to storage, processed in an isolated sandboxed worker, and permanently deleted within 24 hours.