Google Introduces New Image Format - WebP
Google continues its mission to make the web even faster with the introduction of a new web image format - WebP. Based on its VP8 open source codec, the new format promises up to 39% smaller files, which can translate to a much faster web page loading. Google says most of the traffic on the Internet (65%) are mostly photos and images, and helping to reduce file sizes by ~40% will translate to quicker page loading. When we went over to the comparison gallery, we couldn't see any difference.
Note - browsers aren't capable of displaying the current format, so Google has converted the file to PNG for viewing. It can be a little confusing at first, but what you're seeing is the WebP image, but encoded in PNG (hence the bigger file size). Google does provide the original image for download and comparison.