Convert AU to FLAC online in seconds — free, with no sign-up. FLAC is lossless and ideal for archiving and audiophile listening. Your files are encrypted and deleted automatically after 24 hours.
FLAC
Free Lossless Audio Codec — Open-source lossless audio that's 40–60% smaller than WAV with zero quality loss.
How to convert AU to FLAC
- 1Upload your AU file
Click “Choose a file” or drag and drop your AU file onto the page — no sign-up or email needed.
- 2Convert to FLAC
FLAC is already selected as the output. Open Options to fine-tune quality if you like, then click Convert.
- 3Download your FLAC file
Your FLAC file is ready in seconds — click Download to save it. Files are automatically deleted after 24 hours.
Frequently asked questions
Does converting AU to FLAC lose quality?
Converting AU to FLAC keeps your content intact. We use high-quality defaults so your FLAC file looks as close to the original as the format allows.
Is the AU to FLAC converter free?
Yes — converting AU to FLAC is completely free. There's no watermark, no sign-up and no email required, and you can convert as many files as you like.
Are my AU files private and secure?
Yes. Your uploads are encrypted in transit, processed privately, and automatically deleted within 24 hours. We never share, sell or look at your files.
Can I convert AU to FLAC on iPhone, Android, Mac or Windows?
Yes. The converter runs entirely in your browser, so it works on any device — iPhone, iPad, Android, Mac, Windows or Linux — with nothing to download or install.
How long does it take to convert AU to FLAC?
Most files convert in a few seconds. Larger files take a little longer, and your upload speed is usually the limiting factor. There's no queue and no waiting for an email.
What else can I convert AU files to?
Besides FLAC, you can convert AU to AAC, AIFF, M4A, MP3, OGG, OPUS and more — see the full list of AU conversions below.
Other conversions
Last updated July 2026