Do you know your website’s carbon footprint? Or how to lower it? Emissions standards have been set for the automotive, construction, and telecommunications industries, yet the internet’s carbon footprint is growing out of control: a whopping 830 million tons of CO2 annually—larger than that of the entire aviation industry. At least 40 percent of that falls partially under the responsibility of people who make websites. It’s time for web designers to do our part. James Christie explains how to slim our obese websites and simultaneously attack our industry’s carbon footprint, using methods that conveniently dovetail with good business practice and future-friendly design.