MKVMatroska Video
A very flexible video container that can hold several audio tracks and subtitles. Common for films, but some TVs and phones do not recognise it.
Convert MKV to MP4
Turn your MKV videos into MP4 videos right in your browser, so your files are never uploaded to a server. How long it takes depends on the video’s length and your device.
- Files never uploaded
- Free, no sign-up
- No queue
MKV1A45DFA3A3428681
MP40000002066747970
The first bytes of a file often reveal its real format.
or drop them here. You can also paste an image (Ctrl+V).
Free · No sign-up · No upload
Files
These sample files are generated on the page. Convert them to try it out, or add your own.
How to convert MKV to MP4
- 01
Add your MKV files
Click “Choose MKV files” or drop them on the page. You can add several at once.
- 02
Check the MP4 format
MP4 is already selected. You can lower the video resolution: 1080p, 720p or 480p.
- 03
Convert and download
Click “Convert”, then download your MP4 file. With several files, grab everything at once as a ZIP.
MKV to MP4: what to know
MKV is common for films and TV series, and many OBS Studio users record in it because it copes better with a crash. With H.264, HEVC, VP9 or AV1 video and AAC, MP3, Opus or FLAC sound, the picture is copied without re-encoding, and the sound too whenever possible, so it is fast and lossless.
Every compatible audio track is kept with its language and name, such as dubbed and original versions, or OBS’s separate tracks. The MP4 is assembled in memory before it downloads: a few hundred MB go through fine, while a film of several GB may exceed what the browser accepts. Picking 1080p, 720p or 480p makes the file lighter, but the picture is then re-encoded, which takes far longer.
MKV vs MP4: what’s the difference?
MP4MPEG-4 Part 14
The most compatible video format, played by almost every phone, computer, TV and social network.
MKV to MP4: frequently asked questions
What happens if my MKV’s sound cannot be converted?
The audio track is most likely AC-3, E-AC-3 or DTS, formats common in films that this converter cannot carry over. If the MKV has no other sound track, the conversion is refused and a message names the format: no silent file is delivered without your consent. To get the picture alone, choose “Without sound” in the file’s settings, then start again. If the MKV also has an AAC or Opus track, that one is kept and a message names the track left out; otherwise, convert the sound to AAC with a video app first.
Are the MKV’s subtitles and chapters kept in the MP4?
Text subtitles (SRT, ASS or SSA, WebVTT) become subtitle tracks of the MP4, with their language; ASS or SSA ones lose their styling (fonts, colours, positions), and a message says so. Picture subtitles (PGS, VobSub), chapters and attached fonts are not carried over, and a message points them out. For picture subtitles, if you have a separate .srt version, put it next to the MP4 with the same name: many players, VLC included, load it automatically.
Are my MKV files uploaded to the internet?
No. The file is read and converted by your browser, on your device. Nothing is sent to a server, and nothing is kept after you close the page.
Does converting MKV to MP4 reduce quality?
When possible, the video is simply moved into the new container without re-encoding, so nothing is lost. Otherwise your browser re-encodes it at high quality.
How many MKV files can I convert?
As many as you like, for free and without signing up. Add them all, then download the results one by one or in a single ZIP. The maximum size depends on your device and browser, with a few caps that protect its memory (for example 20,000 files per archive or 5 million filled cells per workbook: see the home page FAQ); a file over one of them is not converted, and a message says so.
Does it work on iPhone and Android?
Video conversion uses WebCodecs, a feature of recent versions of Chrome, Edge, Safari and Firefox (except Firefox for Android, which does not have it yet); a video whose picture or sound the browser cannot read or write is refused with a message that says so. On a phone, stick to videos of a few minutes.