Several factors determine why a 720p video ends up at exactly 14.65 MB:
The length of a 14.65 MB file depends on the (the amount of data processed per second). 720p mp4(14.65 MB)
720p is ideal for mobile devices and small monitors, though it may appear "softer" on 4K screens or large displays. Several factors determine why a 720p video ends
Lower bitrates result in smaller files but may introduce "artifacts" or blurriness in fast-moving scenes. 720p mp4(14.65 MB)
A video at 60 frames per second (fps) will be significantly larger than one at 24 or 30 fps because it stores more image data every second.