Website Carbon Calculator estimates a single page's CO₂ emissions. StoreVitals includes a free carbon footprint tool plus continuous monitoring across SEO, security, performance, and accessibility — sustainability as one signal among many.
If sustainability is the primary lens — for a brand campaign, B Corp certification, ESG reporting — Website Carbon Calculator's authority and badge are valuable. If sustainability is one of several health signals you want to track continuously and connect to actual fix workflows, StoreVitals' Carbon Footprint tool plus continuous monitoring covers more ground. The good news: the fixes that lower CO₂ — smaller images, less JavaScript, modern image formats, fewer third-party scripts — are exactly the same fixes that improve LCP, INP, and ranking. Optimizing for emissions and optimizing for Core Web Vitals are the same project. StoreVitals lets you measure both in one place. Use both tools if you want the public-facing badge plus internal monitoring; use StoreVitals alone if internal performance and sustainability tracking is what matters.