FLAC Audio (.FLAC)
FLAC (Free Lossless Audio Codec) is an open-source lossless audio compression format that typically reduces file sizes by 40-60% compared to uncompressed WAV. It preserves the complete original audio data bit-for-bit, allowing perfect reconstruction of the source. FLAC supports high-resolution audio up to 32-bit depth and 655,350 Hz sample rate with embedded metadata and album art.
Advantages of FLAC Audio
What the FLAC format does well, and why you might choose it.
- Completely lossless compression preserving bit-perfect audio quality
- Open-source and royalty-free with broad software and hardware support
- Typically 40-60% smaller than equivalent WAV files
Limitations of FLAC Audio
What the FLACformat doesn't do well, and when to choose another format.
- Still significantly larger than lossy formats like MP3 or AAC
- Not supported by all portable devices and car audio systems
- Encoding and decoding requires more CPU resources than uncompressed formats
What FLAC files are used for
- Audiophile music collections and high-fidelity playback
- Lossless music archival and library preservation
- Source format for transcoding to lossy formats for distribution
How FLAC files work
Audio files store sampled sound: each sample is a measurement of air pressure at a moment in time, and the file is a long sequence of those samples plus metadata (title, artist, cover art). Sample rate (44.1 kHz, 48 kHz, 96 kHz) controls the highest pitch the file can represent; bit depth (16-bit, 24-bit) controls dynamic range. Lossless codecs (FLAC, ALAC, WAV) keep every sample; lossy codecs (MP3, AAC, OPUS, OGG) discard inaudible information using psychoacoustic models. Modern codecs like OPUS achieve near-transparent quality at bitrates where MP3 would sound noticeably degraded.
Best practices when working with FLAC
Record and master in lossless. Encode to lossy only at the final delivery step, and encode from the lossless master, not from another lossy file (re-encoding stacks artifacts). For voice-heavy content like podcasts, 96 kbps mono MP3 or 64 kbps OPUS is plenty; for music, target 192-256 kbps MP3 or 128 kbps OPUS. Don't normalize by clipping — use proper peak/loudness normalization (LUFS targets are -16 for podcasts, -14 for streaming music). Preserve metadata (ID3 tags) when converting if it matters for your library.
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The most common formats people convert to FLAC, ready to convert in seconds.
Convert FLAC to other formats
Convert FLAC Audio files into the format you actually need.
Choosing FLAC versus the alternatives
MP3: universal compatibility, fine for casual listening, 32+ year track record. AAC: better than MP3 at the same bitrate, dominant in Apple's ecosystem and YouTube. OPUS: technically the best modern lossy codec, especially for voice and low bitrates, growing support. FLAC: lossless and free, the de facto archival standard. WAV: lossless and uncompressed, large files but maximum compatibility for editing pipelines. ALAC: Apple's lossless answer to FLAC; choose only inside Apple's ecosystem.
Where FLAC fits in real workflows
Audio production keeps a lossless master (WAV during editing, FLAC for archival) and ships a lossy distribution copy (MP3, AAC, OPUS). Every revision goes back to the lossless master — editing the lossy distribution version compounds compression artifacts in audible ways within just a few generations.
Privacy and file handling
When you convert a FLACfile with MegaConvert, the file is uploaded to our converter, processed, and automatically deleted within an hour. We don't train models on your files, share them with third parties, or retain them after the conversion completes. The download link expires when the file is removed. If your work involves files subject to NDA or compliance requirements (HIPAA, GDPR data processing), please review our privacy policy before uploading sensitive material.
Frequently asked questions about FLAC
What is a .FLAC file?
FLAC (Free Lossless Audio Codec) is an open-source lossless audio compression format that typically reduces file sizes by 40-60% compared to uncompressed WAV. It preserves the complete original audio data bit-for-bit, allowing perfect reconstruction of the source. FLAC supports high-resolution audio up to 32-bit depth and 655,350 Hz sample rate with embedded metadata and album art.
What is the MIME type of FLAC?
The official MIME type for FLAC files is audio/flac. This is the value web servers and applications use to identify the format when transferring files.
What category does FLAC belong to?
FLAC is a Audio Converter format. Files in this category share common conversion paths and use cases.
How do I open a .FLAC file?
FLAC files are typically opened by software that natively supports the FLAC Audioformat. If you don't have a compatible application, the most reliable approach is to convert the file to a more universal format using the converters listed above. Most FLAC Audio files convert to widely-supported alternatives in seconds.
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