Bulk AAC to FLAC Converter Online — Free HD Quality
Drag and drop your multiple AAC files into this 100% free online AAC to FLAC converter (.aac to .flac), and click the Convert button to bulk convert them to FLAC format in HD quality. Use the quality slider to fine-tune your FLAC output, then download your converted files one by one or as a single ZIP — no signup and no downloads needed, and your original AAC files are removed from our servers right after. Also see:Convert WAVE files in bulk to OGG.
Drop your AAC files here to convert to FLAC, or click to browse
Converts .aac to FLAC (.flac) in HD quality — bulk, free, no signup
Choose FilesAAC vs FLAC — File Format Comparison
See how AAC and FLAC compare across file extension, MIME type, compression, and feature support. Related:Process multiple OPUS to AAC files.
| Feature | AAC | FLAC |
|---|---|---|
| File Extension | .aac | .flac |
| MIME Type | audio/aac | audio/flac |
| Compression Type | Lossy | Lossless |
| Metadata Support | Yes | Yes |
What Is AAC Format?
Advanced Audio Coding — the successor to MP3 adopted by Apple, YouTube, and mobile platforms; delivers better quality than MP3 at the same bitrate, especially below 128 kbps. See also:Easy FLAC to WMA converter.
- Compression: Lossy
- Tags & Metadata: Supported
What Is FLAC Format?
Free Lossless Audio Codec — open-source lossless compression that reduces file size by 40–60% versus WAV with zero quality loss, perfect for audiophile archiving. You might also need:Convert PCM to OGG.
- Compression: Lossless
- Tags & Metadata: Supported