Every SINK score is produced by the same formula, using the same rubric, applied to public data. No exceptions. No special treatment. This page explains exactly how it works so you can reproduce any score yourself.
SINK = (0.3 × Base + 0.7 × Performance) × ScaleA fixed score representing the sustainability ceiling of an industry. Oil & Gas scores 20 because the core business is extracting fossil fuels — no amount of solar panels on headquarters changes that. SaaS scores 75 because software has a fundamentally lower environmental footprint. This is a ceiling, not a floor — it caps how high a company in that sector can score.
Ten questions, each scored 0–10, based on publicly available evidence. This is where effort counts. A company that discloses fully, sets science-based targets, transitions to renewable energy, and maintains clean governance will score high regardless of their industry.
Total emissions volume determines a multiplier between 0.60x and 1.00x. A company emitting 50 million tonnes of CO₂e per year has its score reduced by 40% — because scale matters. Physics doesn't care about percentages. The planet experiences absolute tonnes, not relative improvement.
Every company is assessed against these ten questions. Each is scored 0–10 based on the thresholds below. Performance = sum of all ten scores.
New sectors added as companies are scored. Base scores set by editorial review and open to challenge.
Theoretical near-maximum. Requires exceptional performance across all dimensions at scale.
Best-in-class. Only a handful of companies in our database have reached this level.
Genuine sustainability leadership backed by verified data and science-based targets.
Meaningful effort with room for improvement.
Some action but significant gaps remain.
Major disclosure or performance deficiencies.
Minimal effort or actively harmful practices.
We don't grade on a curve. We grade against the planet. Scores above 75 are exceptionally rare — reflecting how demanding the rubric is. The majority of companies score between 30 and 60. A score of 60+ represents genuine sustainability leadership, the kind backed by verified data, science-based targets, and transparent governance.
A separate designation for companies whose core business demonstrably removes more greenhouse gas than it creates. The badge is displayed alongside the SINK score — it does not change the score itself.
Eligibility requires all three:
Scored using publicly available data. Awaiting community verification.
At least 5 community verifications across the 10 questions, with fewer than 3 open challenges.
At least 20 community verifications, fewer than 2 unresolved challenges, and score stable for 30+ days.
Every question on every score has a “Challenge” button. Click it, tell us which tier you think is correct, provide your evidence (a URL or explanation), and submit. That's it.
Challenges are reviewed by the community. If the evidence supports a score change, the score is updated and the challenger is credited publicly. All changes are logged in the score history.
We'd rather be corrected than wrong. That's the point.