This free online FLAC to MKV converter lets you change flac audio files into mkv video format right inside your web browser. There is nothing to install, no account to create and no watermark added to your result.
Unlike most converters, EverythingConverter never uploads your files to a server. The entire FLAC to MKV conversion happens locally on your own device, which means your documents and media stay completely private and the process works even on slow connections.
How to convert FLAC to MKV
- Click the upload area above or drag and drop your FLAC file into it. You can also browse and pick a file from your device.
- EverythingConverter reads the file directly in your browser and starts to convert it to MKV automatically. Nothing is sent to any server.
- When the conversion finishes, your new MKV file downloads right away. You can convert another file at any time, completely free.
FLAC and MKV explained
What is a FLAC file?
FLAC is a lossless audio format that compresses sound without throwing away any data. It keeps perfect CD quality while using about half the space of WAV, which makes it a favorite among audiophiles.
What is a MKV file?
MKV (Matroska) is a flexible open container that can hold video, multiple audio tracks and subtitles in one file. It is popular for high quality movies and archived video.
Convert FLAC to MKV on any device
You can convert FLAC to MKV on Windows, Mac, Linux, Chromebook, Android and iPhone, straight from Chrome, Safari, Edge or Firefox. There is no app to install and no account to create. Because the conversion runs on your own device, it also works offline once the page has loaded, and you can convert as many files as you want.
Frequently asked questions
How do I convert FLAC to MKV for free?
Upload your FLAC file to the converter above and it will be turned into a MKV file automatically. The tool is completely free, with no limits on how many files you can convert and no watermark on the result.
Is it safe to convert FLAC to MKV here?
Yes. EverythingConverter converts your FLAC file entirely inside your browser. Your file is never uploaded to a server, so no one but you ever has access to it. This makes it one of the most private ways to convert FLAC to MKV online.
Can I convert multiple FLAC files at once?
Yes. You can drop or select as many FLAC files as you like and they are all converted to MKV in one batch, then bundled into a single ZIP download. It is the fastest way to bulk convert FLAC to MKV.
Do I need to install any software?
No. The FLAC to MKV converter runs in any modern web browser on Windows, macOS, Linux, Android and iOS. There is nothing to download or install.
Is there a file size limit?
Because the conversion runs on your own device, the practical limit depends on your computer's memory rather than a server quota. Most everyday FLAC files convert instantly, and there is no artificial cap.
How long does it take to convert FLAC to MKV?
For typical files it is almost instant, since the conversion happens locally with no upload or download wait. Large media files take a little longer because your device does the encoding, but there is never a queue.
What is the difference between FLAC and MKV?
FLAC is a lossless audio format that compresses sound without throwing away any data. It keeps perfect CD quality while using about half the space of WAV, which makes it a favorite among audiophiles. MKV (Matroska) is a flexible open container that can hold video, multiple audio tracks and subtitles in one file. It is popular for high quality movies and archived video. Converting FLAC to MKV gives you the strengths of the MKV format for your specific use case.