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Convert MKV to FLAC - Extract Lossless Audio from Video

Extract pristine audio from MKV videos. Perfect quality, zero compression artifacts.

Step 1: Upload your files

You can also Drag and drop files.

Step 2: Choose format
Step 3: Convert files

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Why Extract Audio from MKV as FLAC?

MKV files often contain high-quality audio tracks that deserve better than a lossy MP3 extraction. When your MKV video has a pristine audio track-whether it's a concert recording, film soundtrack, or studio session-converting to FLAC preserves every detail without compression artifacts.

FLAC (Free Lossless Audio Codec) compresses audio to 50-60% of its original size while keeping bit-for-bit accuracy. In our testing, a 2-hour MKV with uncompressed PCM audio produced a FLAC file that was perfectly identical when decoded-no quality loss whatsoever.

How to Convert MKV to FLAC

  1. Upload your MKV file - Drag and drop or click to select your video file
  2. Choose FLAC as output - FLAC is pre-selected for lossless audio extraction
  3. Download your audio - Get your pristine FLAC file ready for any use

The entire process runs in your browser. No software installation, no account creation, no waiting for server processing queues.

MKV Audio vs FLAC: Understanding the Formats

MKV is a container format-think of it as a box that holds video, audio, subtitles, and metadata together. The audio inside an MKV can be encoded in various formats: PCM (uncompressed), DTS, AC3, AAC, or even FLAC itself.

When you convert MKV to FLAC, you're extracting that audio stream and encoding it as a standalone lossless file. Here's how they compare:

  • MKV - Container holding video and audio together, typically 1-50GB for a full movie
  • FLAC - Pure audio, lossless compression, typically 200-600MB for an album
  • Sample rates - FLAC supports up to 655kHz (common: 44.1kHz, 48kHz, 96kHz, 192kHz)
  • Bit depth - FLAC handles 4-32 bits per sample (audiophile standard: 16-bit or 24-bit)

In our testing, extracting audio from an MKV with 24-bit/96kHz PCM audio produced an identical FLAC file. The waveforms matched perfectly under spectral analysis.

Who Needs MKV to FLAC Conversion?

Music Archivists

You recorded a concert and now have MKV files from multiple cameras. Extract the audio as FLAC to create a master archive that preserves every nuance of the performance without video overhead.

Audio Engineers

Need to pull the soundtrack from a video project for remixing or editing in your DAW? FLAC maintains the full dynamic range and frequency response for professional-grade audio work.

Audiophiles

Your Blu-ray rip has phenomenal audio that you want to listen to separately. Convert to FLAC to enjoy the lossless audio track on your hi-fi system without playing the video.

Podcast Producers

Extracting audio interviews or sound bites from video files? FLAC ensures you start with the cleanest possible source before any editing or final export to other formats.

FLAC vs Other Audio Formats

When extracting audio from MKV, you have several output options. Here's why FLAC often makes the most sense:

  • FLAC vs MP3 - MP3 discards audio data to achieve small files. FLAC keeps everything. Choose MKV to MP3 only when file size matters more than quality.
  • FLAC vs WAV - Both are lossless, but FLAC files are 50-60% smaller. MKV to WAV makes sense for maximum compatibility with older audio software.
  • FLAC vs AAC - AAC is lossy like MP3 but more efficient. Still not lossless. MKV to AAC is better for streaming devices with limited storage.

For archiving and editing workflows, FLAC is the clear winner-lossless quality with efficient file sizes.

What Audio Quality to Expect

Your output quality depends entirely on the source audio in your MKV file. We preserve whatever quality exists in the original:

  • Blu-ray rips - Often contain 24-bit/48kHz or 24-bit/96kHz audio. FLAC preserves this perfectly.
  • DVD rips - Typically 16-bit/48kHz. Still excellent quality that FLAC maintains fully.
  • Screen recordings - Usually 16-bit/44.1kHz or 16-bit/48kHz. FLAC keeps the original fidelity.
  • Downloaded videos - Quality varies. Whatever's in the MKV, FLAC preserves it without further degradation.

In our testing, we've converted MKVs ranging from 16-bit/44.1kHz web videos to 24-bit/192kHz audiophile content. FLAC handled all sample rates and bit depths correctly.

When to Choose a Different Format

FLAC isn't always the best choice. Consider alternatives in these situations:

  • Limited storage - If you're extracting audio for a mobile device with little space, MP3 or AAC will be much smaller.
  • Apple ecosystem - Some Apple devices prefer ALAC over FLAC. Though most modern Apple devices now support FLAC natively.
  • Simple playback - If you just want to listen casually and don't care about archival quality, a 256kbps AAC file works fine.

Choose FLAC when quality matters-archiving, editing, audiophile listening, or any workflow where you might need to convert to other formats later.

Batch Conversion for Multiple Files

Have a collection of MKV files from a concert series or multi-episode project? Upload them all at once. Our converter handles batch processing, extracting FLAC audio from each video file without making you repeat the process manually.

This is particularly useful for archiving TV series soundtracks, lecture recordings, or any collection where you want consistent lossless audio across all files.

Works on Any Device

Convert MKV to FLAC directly in your browser:

  • Windows, Mac, Linux, Chromebook
  • Chrome, Firefox, Safari, Edge
  • Tablets and capable mobile devices

No software downloads. No plugins. No registration. Just upload, convert, and download your lossless audio file.

Pro Tip

If your MKV contains DTS-HD Master Audio or Dolby TrueHD, extracting to FLAC preserves the full lossless quality while eliminating compatibility issues with devices that don't decode those proprietary formats.

Common Mistake

Converting to MP3 first for convenience, then regretting the quality loss later. Always extract to FLAC for archiving-you can create MP3 copies from FLAC anytime, but you can't recover lost data from a lossy format.

Best For

Archiving concert recordings, extracting film soundtracks for hi-fi listening, pulling audio from video projects for DAW editing, or any workflow where you might need the source audio again in the future.

Not Recommended

Skip FLAC if you only need background audio for casual listening on a phone with limited storage. A high-quality MP3 or AAC will sound nearly identical in those conditions while using a fraction of the space.

Frequently Asked Questions

No. FLAC is a lossless format, meaning it preserves 100% of the original audio data. When decoded, FLAC produces bit-for-bit identical audio to the source. The only quality limitation is whatever was in the original MKV file.

MKV can contain many audio codecs including PCM (uncompressed), FLAC, DTS, DTS-HD, Dolby TrueHD, AC3, AAC, MP3, Opus, and Vorbis. Our converter extracts the audio stream and encodes it as FLAC regardless of the source codec.

FLAC typically compresses audio to 50-60% of the original uncompressed size. A 100MB PCM audio stream usually becomes a 50-60MB FLAC file with zero quality loss.

Yes, if your phone's browser supports the necessary features. The conversion works on capable mobile browsers, though processing large video files may be slower than on a desktop computer.

FLAC supports sample rates from 1Hz to 655,350Hz and bit depths from 4 to 32 bits per sample. Common configurations include 16-bit/44.1kHz (CD quality), 24-bit/48kHz, 24-bit/96kHz, and 24-bit/192kHz for high-resolution audio.

FLAC preserves all audio data while MP3 discards information to achieve smaller files. Choose FLAC for archiving, audio editing, or when you want maximum quality. Choose MP3 when file size is more important than perfect fidelity.

Most modern audio players support FLAC natively, including VLC, foobar2000, Winamp, and most smartphone music apps. Apple devices added native FLAC support in iOS 11 and macOS High Sierra. Very old software may require a codec pack.

Yes. Upload multiple MKV files for batch conversion. Each video file will have its audio extracted and converted to FLAC individually, saving you from repeating the process for each file.

The converter extracts the primary audio track from your MKV file. If you need a specific secondary track (like a different language), you may need to use the video file's audio track selector before conversion.

Both are lossless and preserve identical audio quality. FLAC files are 50-60% smaller due to compression and support metadata (album art, tags). WAV has broader compatibility with legacy software. For most users, FLAC is the better choice.

Conversion time depends on your file size and computer speed. A typical 2-hour movie MKV might take 30 seconds to 2 minutes for audio extraction. Shorter videos convert proportionally faster.

Yes. FLAC is widely supported by digital audio workstations including Audacity, Adobe Audition, Logic Pro, and Pro Tools. Import your FLAC file directly for editing, mixing, or mastering work.

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