Jake Archibald settles JPEG XL versus AVIF for the web, mostly
After extensive tests, AVIF wins most lossy web images: smaller files and faster encoding and decoding. JPEG XL takes lossless images and the odd outlier. His advice is 4:4:4 AVIF at high effort, a JPEG XL attempt when a file comes out suspiciously large, and testing on your own images.
Jake Archibald

