Animated WebP vs GIF

GIF stores each frame more or less independently, subject to a 256-colour palette. There is some optimisation — storing only the changed rectangle between frames — but nothing resembling motion prediction.

Animated WebP applies the same techniques its still images use: each frame is predicted from what came before, and only the difference is stored. Since consecutive frames of an animation are usually very similar, those differences are small.

The result is commonly a file three to ten times smaller, in full colour rather than 256. It is not a marginal improvement.

The colour limit is what makes old GIFs look the way they do. Any animation involving a photograph, a gradient or a video clip must be quantised to 256 colours per frame, producing banding and — once dithering is applied to hide it — a characteristic speckle that also inflates the file.

WebP has no such limit. And its full alpha channel means an animated overlay can have genuinely soft edges rather than the stair-stepped outline binary transparency forces.

Email. This is the real one. Animated GIF is supported by email clients far more reliably than WebP, which many still do not render at all. For a newsletter, GIF remains the pragmatic choice.

Platforms that expect it. Some services accept GIF uploads specifically, whatever they convert them to afterwards.

Universality outside browsers. Desktop software, chat clients and older systems handle GIF without question.

Note that most "GIFs" on social platforms are already MP4 or WebM behind the scenes — the platforms converted them and kept the label.

For anything beyond a few seconds, a muted autoplaying video is better than either. An MP4 or WebM clip is typically smaller again than animated WebP, decodes with hardware acceleration, and can be paused — which matters for accessibility, since indefinitely looping animation is a genuine problem for some people.

<video autoplay loop muted playsinline>
  <source src="clip.webm" type="video/webm">
  <source src="clip.mp4" type="video/mp4">
</video>

The rule of thumb: under two seconds and simple, animated WebP; longer or complex, video.

This has to be done with real tooling, not a browser. ffmpeg and gifsicle both handle frames, palettes and timing correctly.

A browser canvas decodes only the first frame of an animated GIF, which is why there is no GIF tool on this site — one built that way would silently return a still image and call it compression. That is not a limitation worth papering over.