Zen Convert

Convert FLV to MKV

Free online FLV to MKV converter — no signup, no watermark

Convert FLV (Flash Video) files to MKV (Matroska Video) format online for free. Our FLV to MKV converter runs entirely in your browser — just drag in your file, click convert, and download the result. No software to install, no account required, and your files stay private.

Converting.flvto.mkv
Max 2GB · Files deleted in 1h
Drop your FLV file here
or click to browse — only .flv files accepted

How to convert FLV to MKV in 4 steps

  1. 1

    Upload your FLV file

    Drag and drop your FLV file into the converter, or click to browse from your device. We support files up to 2GB.

  2. 2

    Choose MKV as the output format

    MKV is pre-selected. Optionally adjust quality, resolution or bitrate if your file needs custom settings.

  3. 3

    Convert FLV to MKV

    Click the convert button. Our converter processes your FLV file and produces a high-quality MKV output, usually in under a minute.

  4. 4

    Download your MKV file

    Once conversion is complete, download your MKV file. Your original FLV stays untouched and we delete uploaded files within an hour.

Why convert FLV to MKV?

FLV was the dominant format for web video during the Adobe Flash era. While Flash is deprecated, FLV files still exist in many legacy systems and require conversion to modern formats for playback. MKV is an open-source container format that can hold an unlimited number of video, audio, subtitle and metadata tracks in one file. It's the go-to format for high-quality movie storage and Blu-ray rips. Converting from FLV to MKV is useful when you need high-quality movie storage or want to take advantage of supports unlimited tracks and subtitles.

Top reasons to switch to MKV

  • High-quality movie storage
  • Multi-language video files
  • Blu-ray and DVD archival
  • Files with multiple subtitle tracks

FLV vs MKV: side-by-side

FLV

Pros

  • + Small file sizes
  • + Once-universal web compatibility

Cons

  • Adobe Flash is deprecated
  • No modern browser support
  • Should be converted to MP4 or WebM

MKV

Pros

  • + Supports unlimited tracks and subtitles
  • + Open source and royalty-free
  • + Excellent quality preservation

Cons

  • Not natively supported on iOS or Safari
  • Larger files than MP4
  • Limited streaming support

FLV to MKV — Frequently Asked Questions

Is converting FLV to MKV free?

Yes, our FLV to MKV converter is 100% free. There are no hidden fees, no signups required, and no watermarks added to your converted MKV files.

Will I lose quality converting FLV to MKV?

Our converter uses high-quality encoding settings to preserve as much of the original FLV quality as possible in the MKV output. For lossless results, choose the "high quality" preset.

How long does FLV to MKV conversion take?

Most FLV files convert to MKV in 30 seconds to a few minutes, depending on the file size, duration, and your internet connection. Larger files take longer.

Is it safe to upload my FLV file?

Yes. All uploads use encrypted HTTPS connections, files are processed on isolated servers, and converted MKV files are automatically deleted within one hour of conversion.

Can I convert FLV to MKV on mobile?

Absolutely. Our FLV to MKV converter works in any modern browser on iPhone, Android, iPad, Windows, macOS and Linux — no app install required.

What's the maximum file size for FLV to MKV?

You can convert FLV files up to 2GB to MKV for free. For larger files, contact us about our batch and premium options.

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