Convert M4V to MP4

M4V and MP4: nearly the same thing

An M4V is an MPEG-4 file with Apple's own extension. The iTunes Store sells films and shows as M4V, older versions of iMovie and QuickTime exported M4V for iPhone and Apple TV, and HandBrake can name its MP4 files .m4v. Inside there is H.264 or HEVC video with AAC sound, sometimes with a Dolby Digital track as well. iPhones, iPads and Apple TV boxes play M4V natively, which is why so many Apple-bound exports used it. The difference is mostly in the label: an M4V without protection is built from the same parts as any MP4.

Some programs, TVs and upload forms only look for .mp4. For one unprotected file, renaming .m4v to .mp4 in File Explorer often does the trick. Octoolo does it for a whole folder at once: it copies the picture and sound into a fresh MP4 and leaves the original alone.

Copy-protected iTunes videos

Films and TV episodes bought or rented from the iTunes Store are protected by Apple's FairPlay copy protection. They play only in Apple's apps, on computers and devices authorized with your Apple account. FFmpeg cannot unlock them, so Octoolo cannot turn them into a working MP4. Music from the store has been sold without protection since 2009, but video has not. Rentals expire as well, so there is nothing lasting to convert in any case.

Your own M4V files are a different matter: home movies exported from iMovie, HandBrake copies of your own discs, or videos from other Apple apps carry no protection and convert straight away. If a file plays only in iTunes or the Apple TV app and nowhere else, it is almost certainly protected.

What carries over

M4V files made for Apple TV often pair a stereo AAC track with a 5.1 Dolby Digital one, and the MP4 keeps both. Text subtitles stay text, so they can still be switched on and off in the player, and copying keeps the picture size and frame rate exactly as they were. If the video inside is HEVC and has to play on a PC without HEVC support, convert it to H.264 instead: HEVC to MP4 shows how.

Other ways on Windows

Renaming works for many unprotected files, as above, and costs nothing but a moment. If HandBrake made your M4Vs, its output settings can make it use the .mp4 extension for future encodes, so the question does not come up again. Purchases from the iTunes Store belong in the Apple TV app or iTunes for Windows, where they keep playing. VLC plays unprotected M4V files on Windows as they are, so if you only want to watch one, it may need no conversion at all; for an Android phone or a smart TV, MP4 is the safer label.

For files you already have, Octoolo's converter handles a whole folder in one pass, copies rather than re-encodes, keeps every sound track and never touches the originals. If a file turns out to need re-encoding after all, the line under it says so and names where the work runs.