CarbonLens

Context

Website owners could access sustainability data, but the underlying measurements were technical and fragmented, making it difficult to understand performance or decide what to improve.

Problem

The opportunity was not simply to expose two APIs. It was to translate their outputs into a clear product experience and create a foundation for historical sustainability analytics.

What I built

I built CarbonLens with Next.js, Supabase, the Website Carbon API, the Green Web Foundation API, and Vercel. The current version provides live audits and stores each visitor's ten most recent reports locally through browser cookies without requiring an account.

How it works

1. 01Accept a website URL and retrieve estimated emissions data from the Website Carbon API.
2. 02Check hosting sustainability through the Green Web Foundation API.
3. 03Translate the technical responses into a concise audit explaining performance, meaning, and potential improvements.
4. 04Keep the visitor's ten most recent audits locally so results can be revisited without creating an account.
5. 05Use the current audit experience as the foundation for future traffic, performance, historical emissions, dashboards, reports, and embeddable widgets.

Outcome

• Received more than 1,000 views in one week.
• Combined multiple sustainability sources into one understandable audit.
• Shipped a focused initial product while preserving a path toward a broader analytics platform.

What I learned

Strong product engineering starts with one useful experience. APIs create value only after their data is translated into decisions users can understand and act on.