Resolution
Why 720p is the ceiling
The MP4 is made at the video's own size, capped at 720p (1280×720). That is sharp on any phone and fine on a laptop screen, and it keeps a ten-minute clip to a size you can send in a chat.
Sites that list 1080p, 2K and 4K for every video often hand you an upscaled or silent file. Here the number on the page is the number in the file.
Length
How long a video can be
MP4 works up to about 30 minutes. That covers music videos, Shorts, tutorials, sketches and most vlogs. For a longer video, the clip offers the MP3 instead, which runs to about two hours.
Shorts
Shorts and vertical videos
A youtube.com/shorts/ link works like any other. The MP4 keeps the vertical 9:16 frame, so it plays full screen on a phone and can be posted again as a story or reel, if it is your own clip.
Size
How big the MP4 gets
| 1-minute Short | about 5 to 10 MB |
|---|---|
| Music video, about 4 min | 20 to 40 MB or so |
| 30-minute video (the limit) | about 150 to 300 MB |
Busy, fast-moving footage makes bigger files than a talking head against a wall.
Playback
Opening the MP4
iPhone
In Files, open the clip, press the share arrow, then Save Video; it moves into your Photos library.
Android
The video appears in Google Photos or your gallery app after a moment; it also stays in Download.
Computer and TV
Any player opens it. Copy it to a USB stick and most smart TVs will play it too.
Questions
Questions about the MP4 file
Is the audio included in the MP4?
Yes, picture and soundtrack travel together in one file.
Can I get only part of a video?
No, the whole video is converted. Trim it afterwards in the Photos app or any editor.
Why did my video come out smaller than 720p?
The upload itself was smaller. Nothing is stretched to look bigger than it is.
Checked and updated