GIF and MP4 both show short moving clips, but they work very differently.
- GIF is an image format: it autoplays, loops, and works everywhere without a video player — but it's capped at 256 colours and the files get big fast.
- MP4 is a real video format: full colour, far smaller files and smoother playback — but it needs a video element to play.
A 3-second clip can be 5–10x smaller as MP4 than as GIF. That's why messaging apps quietly convert your GIFs to MP4 behind the scenes.
Convert GIF to MP4 to shrink a file, or video to GIF when you need something that autoplays anywhere.