Convert .mov to .mp4 by changing suffix?

Most programs that can handle one format can also handle the other.

That is why changing the file extension appears to work. For example, if you rename

this.mov to this.mp4, in each case the file may be associated with Quicktime Player, so if you double-click, Quicktime Player launches and opens the file.

However, even though the mp4 and mov containers are very similar (indeed the former was based on the latter), they are not identical.

Just like changing a jpg file extension to png does NOT convert the file, changing mov to mp4 also does not appropriately convert the file.

In the old days, the venerable MPEG Streamclip application could very easily convert between mov and mp4 without reencoding the file.

Nowadays, one would probably use ffmpeg.

Here is an example of a command that would do the conversion:

ffmpeg -i file_example_MOV_480_700kB.mov -c copy -movflags +faststart output-mp4.mp4

I do this every day, it works just fine. If your .mov file is encoded H.264, then simply changing the suffix to .mp4 works just fine. I have a client who can't read files when they're .mov but can when I change them to .mp4. I delver to her weekly, have done so for the past few years, no issues at all, works like a charm every time.

Ian R. Brown wrote:

Thanks Luis.

Would I be correct in thinking that changing the suffix to .mp4 would make it more universally playable?

In macOS or Windows computers, or in iOS or Android devices, I think that both are widely supported, so there will likely be no difference.

I am firmly within the Apple ecosystem, but I think that if you make a movie with H264 codec, whether in mp4 or mov container format, it will play almost universally.