[Dwedit]

WEBP is two image formats bolted together.

First, there's Lossy WEBP, based on VP8 video compression. It is better than JPEG, but mediocre by today's standards. Lossy AVIF and Lossy JXL greatly outclass lossy WEBP.

Second, there's Lossless WEBP, which is not in any way based on VP8. Lossless WEBP is a stellar image format that not only compresses very well, but also decompresses very quickly. Its biggest competition is Lossless JXL, which usually compresses to a smaller file, but decoding that image is slow enough to be annoying. Sometimes lossless WEBP produces a smaller file than lossless JXL.

[JyrkiAlakuijala]

Thank you. I agree with the sentiment that WebP lossless has stand the test of time better than WebP lossy. In some comparisons even Jpegli is more attractive from compression density point view than WebP lossy.

Disclaimer: I am the designer of WebP lossless and Jpegli.

[kevincox]

Yes, you are right that the lossless format is much more notable but also much less common than the lossy one. It is quite an improvement over PNG which is the only real competitor on the web.