MP4 vs MOV
MP4 was built on Apple's QuickTime file format, so the two are close relatives. The same video can live in either with no difference in quality.
| MOV (QuickTime) | MP4 | |
|---|---|---|
| Origin | Apple, 1991 | ISO standard (2001), based on QuickTime |
| Typical codecs | H.264, HEVC, ProRes, PCM audio | H.264, HEVC, AV1, AAC audio |
| ProRes / PCM | Yes, natively | No |
| Windows & Android | Plays in most apps; some web forms refuse .mov | Plays everywhere |
| Quality | Same as MP4 for the same codec | Same as MOV for the same codec |
| Size | Same for the same streams | Same for the same streams |
| Best for | Apple editing workflows, ProRes intermediates | Sharing, uploads, the web |
Switching between them
MOV to MP4, and back, is almost always a remux: the H.264 or HEVC stream is copied into the other container without being touched. The catch is HEVC: an iPhone HEVC clip stays HEVC after remuxing, so if a Windows PC or web app still refuses it, re-encode to H.264.
Questions
Why do iPhones record MOV instead of MP4?
MOV is Apple's QuickTime format and it supports Apple-specific metadata (Live Photo pairing, some camera data). The video inside is the same HEVC or H.264 that an MP4 would hold.
Can I just rename .mov to .mp4?
Often it works, because both use the same ISO base media structure, but some MOV-only features can confuse players. A proper remux rewrites the header correctly and takes seconds.
Which is better for editing?
For H.264/HEVC, neither. For heavy editing, ProRes in MOV is easier on your computer because each frame is compressed on its own.