Video conversion
Convert FLV to MKV
FLV is the old Flash based format many web videos were saved in, and MKV is a modern container that plays cleanly in today's media players. To convert FLV to MKV, open the file in a converter and export it as MKV, right on your own computer without uploading anything.
All 2,748 conversions verified on macOS, Windows, and Linux against the shipping release, this one included. Every conversion runs entirely on your own computer.
- Extension
- .flv
- Type
- Video
- Typically
- Legacy web video
- Compression
- Lossy
- Extension
- .mkv
- Type
- Video
- Typically
- High-quality video containers
Convert FLV to MKV on your own computer. Nothing uploads.
One-time purchase, no subscription. 14 days to change your mind.
How to convert FLV to MKV
- Open Morphjet and drag in the FLV file, or a whole folder of old FLV clips, at once.
- Choose MKV as the output format.
- Convert. The MKV file is written right next to your original, and nothing leaves your machine.
FLV vs MKV: what actually changes
| FLV | MKV | |
|---|---|---|
| File size | Small, thanks to old, aggressive compression | Somewhat larger, since MKV doesn't add extra compression on export |
| Quality | Lossy, using dated codecs from the Flash era | Matches the source, MKV is just a container, not a fresh layer of compression |
| Compatibility | Poor, most modern browsers and phones dropped Flash support years ago | Wide support in modern media players and TVs |
| Multiple audio and subtitle tracks | No, one video and one audio stream only | Yes, can hold several audio tracks and subtitle files in one file |
| Metadata | Minimal | Can store rich metadata, chapters, and track info |
When to convert, and when not to
Convert FLV to MKV when you've found old Flash era video files and want to play them on a modern computer, TV, or media player that no longer supports Flash.
Keep the FLV if it's just sitting in an archive you never plan to open again, since converting it doesn't recover quality that the original compression already threw away.
Why not just use an online converter?
Old FLV files often come from downloaded lectures, personal recordings, or saved web videos, the kind of thing you might not want sitting on someone else's server. Uploading them to an online converter means a stranger's server holds a copy while it works, and there's no way to know how long it stays there. Converting on your own computer means the video never has to leave your machine.
Questions
Does converting FLV to MKV improve the video quality?
No. FLV's original compression already set the quality ceiling, and no amount of converting reverses that. MKV just gives the video a more modern, more compatible home.
Why won't my FLV file play anymore?
Flash was phased out by browsers and most devices years ago, and FLV was Flash's native video format, so a lot of players simply dropped support for it. MKV doesn't have that problem.
Does MKV keep multiple audio tracks or subtitles from the original?
MKV is built to hold several audio tracks and subtitle files in a single file, but FLV usually only had one of each, so there's rarely anything extra to carry over.
Can I convert FLV to MKV without uploading it anywhere?
Yes. A desktop app like Morphjet converts the file on your own computer, so it never has to travel over the internet.
Morphjet runs this conversion and 2,747 others, all on your machine. Available now.
One-time purchase, no subscription. 14 days to change your mind.