Tiny Beest Image Optimization is a free Chrome extension which enables reducing the size of web images before they're downloaded.

Once it's installed, right-click an image and you'll see a Tiny Beest Image Optimization menu option.

Choose this item and you're able to resize the image to one of several standard sizes (1920px, 1440px, 1280px, 1080px, 600px, 300px).

The package also uses other techniques to cut image size, including reducing the quality settings, and if you don't want to resize the source picture then an "Optimize current size" option uses these techniques only.

Our tests showed the extension generally delivered very good results. Even without resizing, large and complex images were often much smaller (2MB > 500KB, say), and even smaller simpler web photos saw significant falls (80KB > 50KB). This comes at the cost of reduced image quality, but it's not something you'll likely to notice in most situations.

There's a small privacy issue in using the tool. Your images are optimised on Tiny Beest's server, which logs details of the image and links them to your IP address. We don't see that as harmful or surprising - the developer (a web design company) needs to log this to detect and block automated attempts to use the service - but you might want to keep it in mind.