Serve images in next-gen formats
What are next-gen formats
Image formats like JPEG 2000, JPEG XR, and WebP which often provide better compression than PNG or JPEG, which means faster downloads and less data consumption. The Opportunities section of your Lighthouse report lists all images in older image formats, showing potential savings gained by serving WebP versions of those images:
Why serve images in WebP format
JPEG 2000, JPEG XR, and WebP are image formats that have superior compression and quality characteristics compared to their older JPEG and PNG counterparts. Encoding your images in these formats rather than JPEG or PNG means that they will load faster and consume less cellular data.
WebP is supported in Chrome and Opera and provides better lossy and lossless compression for images on the web. See A New Image Format For The Web for more on WebP.
