AU to FLAC Converter
Convert AU to FLAC Online Free.
Convert AU to FLAC Online Free
Loading available formats…
AU
AU is a simple audio format introduced by Sun Microsystems. It stores audio with a short header, often as µ-law or uncompressed PCM, and was common on Unix systems and early web pages. Today AU files are rare, so they are usually converted to WAV or MP3.
FLAC
FLAC (Free Lossless Audio Codec) is a lossless audio format that compresses music and recordings without removing any audio data. It keeps the original sound quality intact while usually using much less storage than uncompressed WAV. FLAC is popular for music libraries, archiving, hi-fi playback, and converting to other audio formats later.
What happens when AU becomes FLAC
Source format
AU is the audio source or target format for this conversion path.
Target format
FLAC compresses audio without discarding decoded sample data.
What changes
Audio samples are decoded from AU and encoded according to the FLAC format and selected bitrate or quality.
- What is preserved
- Duration and audible content are preserved, subject to decoder support and any settings you change.
- What may be lost
- Tags, embedded artwork, chapters, and codec-specific metadata may not map to FLAC.
- Codec and quality implications
- Inspect the output before replacing the source, especially when the formats use different layout, codec, or editing models.
- Realistic limitations
- Protected audio, malformed headers, unsupported codec variants, or files without a decodable audio stream cannot be converted.
Conversion steps
- Upload a AU file no larger than 1 GB.
- Confirm that FLAC is selected as the target.
- Start the conversion. A healthy compatible worker begins processing immediately.
- Download the FLAC file and check the result before deleting your source.
Troubleshooting
- The AU file is rejected or will not open.
- Confirm that the file is not empty, password-protected, or corrupt and that its real format matches the extension.
- The FLAC file is larger than expected.
- Choose a more efficient codec or lower quality setting when available. Lossless and uncompressed targets are often larger by design.
- The result has no sound or will not play.
- Try a broadly supported target codec and verify that the source contains a decodable audio stream.
Privacy and file retention
Uploads and converted files are processed automatically and irreversibly deleted within 24 hours. You can delete them sooner with the delete control. Convertr does not read, mine, sell, or manually review file contents.
Read the privacy policy