Turn M4V files into MP4
Convert an M4V into an MP4 right here on the page. M4V is the Apple version of an MP4, and the two are close enough that converting between them is quick and costs no quality. The practical difference is that the result opens anywhere, which M4V files do not. Your file never leaves your computer.
Need the other direction? Convert MP4 to M4V
How to convert M4V to MP4
- 1 Drop your M4V .m4v file onto the page, or click to browse for it.
- 2 Set the quality, or leave the default, which keeps the file small without anything showing.
- 3 Convert. The work happens on your own machine, so how long it takes depends on your computer and the file.
- 4 Download the MP4, or add more files and do the whole set in one go.
Why convert M4V to MP4
- An M4V will not open in a browser, so anything going onto a web page, into a document or into a message has to become an MP4 first.
- Plays on effectively every device, browser and TV made this century.
- Plays without draining the battery, because devices handle it natively.
- Anything that simply has to play, wherever it is opened.
- M4V: fairPlay protected files cannot be converted.
M4V compared with MP4
How the two formats differ on the things that decide whether a conversion is worth making.
| Property | M4V | MP4 |
|---|---|---|
| File extension | .m4v | .mp4 |
| Browser support | Some browsers | Every browser |
| Introduced | 2005 | 2001 |
| Developed by | Apple | ISO/IEC MPEG |
| Standard | Proprietary | Open |
Quality and what changes
Both formats are lossy, so this is a second generation of compression: the M4V is decoded back to pixels that already carry its artefacts, and MP4 then compresses that. The damage compounds rather than cancelling out, which is why repeated round trips visibly degrade an image. Encode at a higher quality than the source used, and convert once from the best copy you have rather than from an already converted file.
- Files protected with DRM cannot be decoded and will fail rather than convert.
- One MP4 limitation to keep in mind: playing and distributing it carries patent licensing obligations.
Questions about M4V to MP4
Will converting M4V to MP4 lose quality?
A little. Both formats are lossy, so the file is decoded and compressed a second time and the two sets of artefacts add up. At a high quality setting the difference is hard to see, but avoid repeated round trips between lossy formats.
Is my M4V file uploaded anywhere?
No. The whole thing runs inside the browser tab you already have open. Your M4V is read straight from your own disk, converted on your machine and handed back as an MP4. Nothing is sent anywhere, nothing is stored and there is no account.
Is there a file size limit?
There is no server-side limit because no server sees the file. The real ceiling is your device memory, since the input and the output both have to fit in the tab. A few hundred megabytes is usually fine on a desktop machine and considerably less on a phone.
Can I convert several M4V files at once?
Yes. Add as many as you like and they are processed one after another, then offered as separate MP4 downloads or as a single ZIP. Speed depends on your own processor rather than on a queue.
Does the converter work offline?
Yes, after the page has loaded once. The engine is cached by the browser, so you can disconnect, reload and keep converting. That falls out of doing the work locally rather than being a separate mode you switch on.