MOV to MP4
In your browser, no upload
MP4
rewrapped · not re-encoded
Video
MOV · M4V → MP4Specification
7 rows| Item | Value | Notes |
|---|---|---|
| Input | MP4, MOV, M4V | Read from the file itself, not its name |
| Output | MP4 | The same tracks in an MP4 container |
| Length | Unchanged | Nothing is cut |
| Quality | Untouched | Nothing is decoded or encoded |
| Sound | Kept | The sound track is copied too |
| File size | No limit | Only the file’s index is read; the picture stays on disk |
| Processed in | This browser | Not sent to a server |
What happens
3What happens, and why
MOV and MP4 are the same format. QuickTime wrote the specification, ISO adopted it as MP4, and the boxes inside the two files are laid out the same way — which is why one tool reads both and why a converter is not needed here. What differs is the four letters near the front of the file that say which one it is, and a handful of habits QuickTime has that MP4 readers do not expect.
So this page does not convert anything. It reads where every frame and every sound packet is, writes a new index in MP4’s own dialect, and copies those bytes across untouched. A file that a program refused because it ended in .mov opens, at the same quality, usually in about a second.
What a phone stores in the file comes with it: the display matrix that says a clip is portrait, the sound track, the frame timings. Tracks that are neither picture nor sound — the timecode track an iPhone writes, for instance — are left out, and the line under the result says so when there were any.
FAQ
4Is this a real conversion
No, and that is the point. The video inside a MOV is normally H.264 or HEVC, which is exactly what an MP4 holds. Re-encoding it would take minutes and lose quality to no purpose. This rewrites the container around the same frames instead.
Why did my player refuse the .mov then
Usually because of the extension and the brand at the front of the file rather than the video inside it, and sometimes because of QuickTime habits an MP4 reader does not expect — a handler name written the QuickTime way, a Macintosh language number where a three-letter code belongs. Those are what this page rewrites.
Will my portrait clip stay portrait
Yes. A phone records in landscape and writes a rotation into the track header; that box is copied across, so a player turns the picture the same way it did before.
Is the video uploaded
No. The browser reads the file from your disk and writes the new one on this page. There is no upload endpoint on this site, so there is nowhere for the file to go.