MKV to M4V Converter

What happens when you convert MKV to M4V

• If the video inside the MKV is already H.264, the tool first copies the streams straight into the M4V. That takes seconds and loses nothing.
• If a copy is not possible, it re-encodes to H.264 video with AAC audio, which is slow in a browser: expect several times the video's length for HD footage, less at lower resolutions.

How to convert MKV to M4V online

1. Press "Choose MKV files" and select one or more files, or drag them onto the box. You can add files of any size your device can hold in memory.
2. Adjust the settings if you need to: resolution and quality control the size of the result. The defaults suit most people.
3. Press "Convert to M4V". The first audio or video conversion downloads the converter engine, about 32 MB, which your browser then keeps for next time.
4. Save each M4V with its download button. Close the tab and every trace of the files is gone from memory.

Why convert MKV to M4V?

MKV files usually come from films and TV rips, OBS recordings and anime releases. People convert them to M4V because M4V is the format Apple devices and iTunes use for video libraries.

In short, MKV is good at what it was made for, and M4V is the more practical choice when the file has to play, upload or edit somewhere else. Chrome and Edge play many MKV files; Safari and iPhones do not, while M4V plays in Safari; Chrome plays unprotected M4V files.

How to convert MKV to M4V on Windows, Mac, iPhone and Android

On Windows

Open this page in Chrome, Edge or Firefox, drag your MKV files in from File Explorer, and press Convert. Each M4V is saved to your Downloads folder. If you prefer a desktop program, VLC can also convert MKV to M4V: choose Media, then Convert / Save.

On a Mac

Safari, Chrome and Firefox all work. Drag the MKV files from Finder onto the drop zone and the M4V files land in Downloads.

On iPhone and iPad

Open the page in Safari and tap Choose MKV files. You can pick from Photos or from the Files app. The converted M4V appears in Files, in the Downloads folder; to put it in your photo library, open it there, tap Share and choose Save Video.

On Android

Open the page in Chrome, tap Choose MKV files and pick them from Files or your gallery. The M4V is saved to the Download folder, where any file manager can find it. Keep the screen on while a long video converts, because Android may pause a tab in the background.

Best settings for MKV to M4V

Leave Resolution on Keep original and Quality on Standard if the video only needs to change container: that is what lets the tool copy the H.264 stream straight into the M4V, which is fast and loses nothing.

If the file is too big, change either setting and the video is re-encoded with H.264. Quality uses the CRF scale: High is 20, Standard 23 and Smaller file 28. As a rule of thumb each step of about 6 on that scale halves or doubles the size. Dropping from 1080p to 720p usually saves more than lowering the quality, and it also makes the conversion much faster.

MKV vs M4V: the differences

About MKV and M4V files

What is an MKV file?

MKV can hold unlimited audio tracks, subtitle tracks and chapters in one file, which is why film rips use it. OBS offers MKV recording because a crash part way through does not corrupt the whole file.

What is an M4V file?

M4V is nearly identical to MP4. Files bought from iTunes carry FairPlay copy protection, which no converter can legally remove; unprotected M4V files convert freely.

MKV to M4V not working? Common problems

• The conversion is slow. Audio and container changes take seconds, but re-encoding video runs on your own processor. Lower the resolution to 720p, close other tabs, and keep the device plugged in.
• The tab stops or reloads on a very large file. Browsers limit how much memory one tab can use, around 2 GB and less on phones. Split long recordings or convert them on a computer.
• The M4V will not play on an old device. Try the other formats offered for MKV, or choose 720p, which older players handle more reliably.

Convert MKV to M4V with ffmpeg

This converter runs ffmpeg inside your browser. If you would rather use the ffmpeg command line on your own computer, this command produces an equivalent M4V with the same kind of settings:

ffmpeg -i input.mkv -c:v libx264 -crf 23 -c:a aac -b:a 128k -f mp4 output.m4v

Replace input.mkv with the name of your file. For a whole folder of MKV files, run the command in a loop, or drop them all on the converter above, which processes them one after another.