AVIF is an even newer image format than WebP—developed based on the AV1 video codec. It compresses images significantly more than WebP while maintaining comparable or better quality: AVIF files are typically 20–50% smaller than WebP files. AVIF really shines with photos that have a lot of detail. Browser support is good, but not yet universal—older browsers like Safari versions prior to 16 do not support AVIF. For maximum compatibility, a combination is recommended: AVIF as the primary format, WebP as a fallback. WordPress has supported AVIF since version 6.5.