Convert FLV to MKV
FLV is great for old web video archives, but MKV is the better choice for movies with multiple audio tracks and subtitles. Convert FLV to MKV in seconds, right in your browser.
- No upload — 100% private
- Fast, lossless when possible
- Free & unlimited
- Works on iPhone & Android
Keep this tab open — the conversion runs on your device, nothing is uploaded.
Add more files above to keep converting.
How to convert FLV to MKV
- 1
Tap Choose files and select one or more FLV files (or drag them in).
- 2
Check that MKV is selected. Use Advanced options for resolution, size or trimming.
- 3
Press Convert. Everything happens on your device — no upload, no waiting in a queue.
- 4
Your MKV downloads automatically. Converting several files? Grab them all as a ZIP.
FLV vs MKV
Both formats are lossy, so the video is re-encoded once. Pick High quality to keep it as close to the original as possible, or Small for the smallest file.
| FLV | MKV | |
|---|---|---|
| Full name | Flash Video | Matroska Video |
| Type | Video | Video |
| Compression | Lossy | Lossy |
| Developed by | Adobe | Matroska.org |
| Introduced | 2002 | 2002 |
| Plays on iPhone | ✕ No | ✕ No |
| Plays on Android | ◐ Partly / with an app | ◐ Partly / with an app |
| Plays on Windows | ◐ Partly / with an app | ✓ Yes |
| Plays on Mac | ✕ No | ◐ Partly / with an app |
About FLV and MKV
FLV: FLV is the Flash Video format that powered early YouTube. Flash is gone, so FLV files usually need converting to play today.
MKV: MKV is a flexible open container that can hold unlimited video, audio and subtitle tracks. It is popular for movies and anime but isn't supported by iPhone or most TVs out of the box.
Frequently asked questions
How do I convert FLV to MKV on my phone?
Will converting FLV to MKV reduce quality?
Is this FLV to MKV converter free?
Are my files uploaded to a server?
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