A large bundle size is the biggest fear to any JavaScript developer, but who knew a large bundle size affects more than your user experience? A large bundle also means that the CO2 footprint of your website is also bigger, as larger bundles need more bandwidth and resources. In 2020 the average website was 4 times bigger than 10 years before, what are the climate effects of this? In this talk I'll show how your website is impacting the climate, and how you can (and should) change this.