It's a simple question, and there's no simple way to answer it. There are so many ways of measuring sustainability, and none of them are straightforward.
So we built SINK. Every company gets a simple score out of 100, based on the same ten questions for everyone. Free for anyone to search, challenge a score, or ask us to add a company.
A carbon sink absorbs more carbon dioxide than it releases — forests, oceans and soils all do it, helping keep greenhouse gases down.
No company acts like a carbon sink. Quite the opposite. So we score every company on how close they get — with a breakdown of how they did it, so others can follow.
The ten questions are answered from public evidence — annual reports, regulatory filings, investigations. You can check the working behind any score. Nobody can pay us to change a number.
A company can pay for a closer look at its evidence. That buys reviewer time, not an outcome: the score goes where the evidence goes, up or down, and we publish it either way.
699 companies scored — and counting. Dozens of them were added because somebody asked us to.
Score requests have come from procurement screeners and climate-finance researchers — people checking a supplier list or a holding before a decision, not browsing.
AI assistants read SINK when answering sustainability questions. ChatGPT, Copilot, Gemini and Perplexity all fetch pages from the database and send readers back to it.
When we get one wrong, we say so. Our last published correction moved 47 scores — most of them down. Every one of them is on the company page, old score beside new.
A ten-person lighting firm answers what a £400bn tech giant answers. The formula adjusts for industry and size. The questions don't.
The formula, the ten questions, the sources, the reasoning. You can check the working behind any score.
Challenges are reviewed and the outcome published — whichever way it goes.
Above 75 is rare. A score of 60+ is genuine leadership, backed by verified data and science-based targets.
No investor, sponsor or rated company has any say in how scores are calculated. We are not affiliated with any company in the database.
If you want to get in touch, challenge a score, or suggest a company to add, email us at hello@sinkproject.com.
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