Skip to content
ConvertAnyVideo

FLV to MKV Converter

Convert FLV videos to MKV in seconds. Change resolution, quality and frame rate if you like — all in your browser.

or drop files here

Up to 1 GB per file · Files never leave your device

  • 100% free
  • No sign-up
  • No upload — private
  • No watermark

How to convert FLV to MKV

  1. Add your FLV files

    Click “Choose Files” or drag and drop your FLV videos onto this page.

  2. MKV is selected

    The output is already set to MKV. Open Advanced settings if you want to change the quality, resolution or length.

  3. Convert and download

    Click Convert. Your MKV file is ready in moments — nothing is uploaded.

About the formats

FLV

Flash Video

FLV was the format of Flash video players. It is still used by some streaming tools and old web videos.

MKV

Matroska Video

MKV (Matroska) is a flexible open container that can hold several audio tracks, subtitles and chapters in one file. It is popular for movies and series.

Frequently asked questions

How do I convert FLV to MKV?

Click “Choose Files” and select your FLV file (or drag it onto the page). MKV is already selected as the output, so just click Convert and download your MKV file when it’s ready.

Will I lose quality converting FLV to MKV?

When the video inside your FLV file is compatible with MKV, it is copied without re-encoding, so there is no quality loss at all. Otherwise it is re-encoded at high quality. You can pick the quality yourself in Advanced settings.

Is it safe to convert FLV files here?

Yes. Conversion runs inside your own web browser, so your files are never uploaded to our servers or anyone else’s. Nobody can see them, and nothing is stored after you close the tab.

Is the FLV to MKV converter free?

Yes, it’s completely free. There’s no sign-up, no watermark and no limit on how many files you convert. Each file can be up to 1 GB.

Can I convert several FLV files at once?

Yes. Add as many FLV files as you like and convert them in one go, then download them one by one or together as a ZIP file.

Convert FLV to other formats

Convert other formats to MKV