WEBP to AVIF Converter

WEBP to AVIF is for sites that already did the optimization work once and want the next increment. If your images shipped as WEBP years ago, re-encoding them as AVIF typically buys another 20-30% off each file at the same visual quality - meaningful at scale, and the kind of improvement that shows up directly in LCP timings on image-heavy pages.

ImgShifter handles both ends locally: your browser's native WEBP decoder reads the source, and a cached ~300 KB WebAssembly encoder writes the AVIF, transparency included. The honest caveat of any lossy-to-lossy conversion applies - if you still have the original PNGs or camera files, encoding AVIF from those preserves slightly more detail than converting the WEBPs.

You don't have to choose one format globally: the HTML picture element serves AVIF to browsers that support it and falls back to WEBP for the rest, so converting is purely additive. Everything here runs offline once the page has loaded - no upload, no signup.