Pages grow by accretion: a slider plugin here, a second copy of jQuery there, full-size images everywhere. Every visitor downloads all of it, on every first view.
The fix you can use today
Measure a first view: bytes and requests, with a real browser.
Remove scripts a page does not use and purge unused CSS.
Recompress images, serve WebP or AVIF, and lazy-load what is below the fold.
That is GreenCode's own website, measured before and after the rebuild.
Tools that help
Lighthouse: audits a page for total byte weight, unused JavaScript and CSS, image formats and offscreen images
WebPageTest: loads a real page and shows every request, its size and when it loaded
CO2.js (Green Web Foundation): an open-source library that turns bytes transferred into an estimate of CO2, using the Sustainable Web Design model
How GreenCode helps
GreenCode helps tackle this by practising it on greencode.ai: static pages, WebP images, scripts only where they are used and purged styles cut a first view of the home page from 80 requests to 33. More on this.
