For the last few years Google have been working on reducing file sizes of images on the web and now they seem to have reached a point where they succeeded in a big way.
In their blog post, Google say that they developed a new algorithm called Guetzli, which can reduce the file size of JPEGs by 35%.
That’s what Google have to say about that:
Guetzli [guɛtsli] — cookie in Swiss German — is a JPEG encoder for digital images and web graphics that can enable faster online experiences by producing smaller JPEG files while still maintaining compatibility with existing browsers, image processing applications and the JPEG standard.
So they manage to create much smaller files without compromising the quality of images.
Here’s an example with original image on the left and Google’s compressed image on the right:
image source: Google Research blog