When it comes to short looping animations, three formats dominate the conversation: GIF, WebP, and MP4. Each has a different history, different strengths, and different reasons to use or avoid it depending on what you're doing.
GIF: the universal option
GIF is from 1987. It was designed for simple graphics with limited colors and small file sizes back when the internet was slow. By modern standards it's inefficient, it only supports 256 colors per frame, has no real compression for video content, and produces large files for anything complex. But it works everywhere. Every platform, every email client, every messaging app built in the last 30 years supports it. That's why it still dominates for animated reaction content.
WebP: the smart choice for the web
Google developed WebP as a modern image format that handles both static and animated content efficiently. Animated WebP files are typically 3 to 5 times smaller than equivalent GIFs. They support millions of colors and full transparency. TikTok uses WebP for stickers because the bandwidth savings at scale are significant. The downside is support outside of browsers is still patchy. Most native apps and older platforms don't handle animated WebP files.
MP4: best compression, worst flexibility
For pure compression efficiency, MP4 wins easily. A 2MB GIF might be 100KB as an MP4. Modern platforms like Twitter and Tenor actually convert uploaded GIFs to MP4 behind the scenes and serve them as silent looping video. The problems with MP4 for this use case are that it doesn't support transparency, it requires video playback infrastructure rather than simple image display, and autoplay behavior varies across platforms.
Which should you use
For sharing in chats, reactions, or uploading to GIF platforms, GIF is still the safest choice because of universal compatibility. For your own website or a platform where you control the tech stack, WebP animated or MP4 will give you much smaller files. For video content with sound, MP4 every time. StickerToGIF converts to GIF specifically because that's what works everywhere a TikTok sticker might end up.