Format at a glance
- Full name
- Free Lossless Audio Codec
- File extensions
- .flac
- MIME types
- audio/flac
- Category
- Audio
- Compression
- Lossless
- Transparency
- Not applicable
- Animation
- Not applicable
- Properties
Suitable tools
What is this format?
FLAC means Free Lossless Audio Codec and names both the codec and its common native file format. Prediction and residual coding reduce size without discarding audible information.
FLAC files can contain Vorbis comments, embedded artwork, checksums and seek tables. They are normally much smaller than uncompressed PCM WAV.
What is it used for?
- Lossless music libraries
- Archiving CDs and recordings
- Exchanging high-quality audio
- Intermediate files before editing or conversion
Which programs can open it?
- VLC, foobar2000 and MusicBee
- Audacity and FLAC-capable DAWs
- FFmpeg and music servers
- Mobile music apps with FLAC support
Support across devices and browsers
FLAC opens in VLC, suitable system codecs and many audio applications.
QuickTime, music applications and VLC support FLAC depending on the contained codec.
VLC, mpv, FFmpeg and common audio players handle FLAC.
Playback depends on the device, Android version and contained codec.
Apple applications support common combinations; other variants need a compatible app.
Direct playback depends on browser and codec; LocalFileLab can additionally use FFmpeg/WebAssembly.
Advantages
- Bit-perfect lossless reconstruction
- Good compression for PCM audio
- Open format with metadata and checksums
Disadvantages
- Larger than lossy MP3 or AAC
- Not supported by every older hardware player
- Repeated compression provides no quality improvement
Comparison with alternatives
PCM WAV is simpler and larger; FLAC stores the same samples much more compactly.
MP3 is smaller and universal but permanently removes audio information.
OGG is a container often carrying Vorbis or Opus, while FLAC describes lossless audio compression.
LocalFileLab support
FLAC is recognized as an input. Audio is read through browser features or FFmpeg/WebAssembly depending on the codec.
FLAC is available as a local output; available settings depend on the format.
LocalFileLab can compress FLAC locally or package it in a supported archive; already compressed content will not necessarily become smaller.
A local preview is available when the browser can display or play the content.
Existing metadata can be retained or removed depending on the selected path.
Container and codecs
The LocalFileLab statements below come from the FFmpeg/WASM and WebCodecs paths actually configured in the repository. Decoders or tracks not explicitly evidenced in code are marked unverified.
- Container
- Native FLAC Bitstream
- Typical video codecs
- Typical audio codecs
- FLAC
| Codec | Type | Input | Output | Notes |
|---|---|---|---|---|
| FLAC | Audio | Unverified | Supported | The project does not enumerate the FFmpeg/WASM input decoder per codec. A concrete FFmpeg/WASM encoder is configured in the repository. |
Tracks and metadata
- Subtitle tracks
- Unverified
- Multiple audio tracks
- Not supported
- Chapters
- Unverified
- Metadata
- Configurable
Known combinations
Related formats
Frequently asked questions
Does FLAC lose quality during conversion?
The FLAC process itself is lossless. Quality is lost only when the source or target uses lossy encoding.
Is FLAC better than WAV?
FLAC is usually more space-efficient for archiving and supports useful metadata. WAV remains exceptionally straightforward in some production workflows.
Can FLAC contain album artwork?
Yes. FLAC supports embedded pictures and Vorbis-comment metadata; preservation depends on the selected conversion path.