Understanding quality scoring
The five quality dimensions in depth, how the composite grade is computed, and what provisional means for every score.
Why quality scoring exists
The voluntary carbon market has a structural problem: buyers cannot easily tell strong credits from weak ones. CarbSet closes that gap by scoring every credit against five dimensions and mapping the result to a single, comparable grade. This article explains how that works and, just as importantly, what it does not yet mean.
All quality assessments on CarbSet are currently provisional. This means scores have not yet been independently verified by an external assessor. A Provisional badge is shown wherever a grade appears.
CarbSet's independent scoring authority is still being established. The methodology and the grades are real and considered, but the external verification layer that would make a grade fully authoritative is not yet in place. Read every grade in that light.
The five dimensions
Each credit is scored on five dimensions, each from 0 to 100. They are weighted equally, so no single factor can dominate the headline grade.
Additionality
Additionality asks whether the emissions reduction or removal would have happened without the credit revenue. If a project would have gone ahead anyway (for example because it was already profitable or legally required), the credits it sells are not adding new climate benefit. A high additionality score means the project genuinely depends on carbon finance and passes a credible test of what would otherwise have occurred.
Permanence
Permanence measures how durable the outcome is. Removing carbon into a forest is valuable, but only if the forest stands. A project exposed to reversal risk (fire, disease, harvesting, or land-use change) scores lower unless it holds strong safeguards such as buffer pools. Geological or long-lived storage tends to score higher than nature-based storage that can be released.
Measurement
Measurement covers how accurately the impact is quantified. This includes the quality of the monitoring data, the rigour of the methodology, the conservativeness of assumptions, and whether the project avoids over-crediting. Strong measurement means the tonnes claimed are the tonnes delivered, with little room for inflation.
Co-benefits
Co-benefits capture the value a project delivers beyond carbon: biodiversity protection, clean water, community income, gender equity, education, and health. These are recorded against the project and contribute to the score. A credit with strong, evidenced co-benefits is worth more than a bare tonne of avoided emissions.
Verification
Verification reflects the strength of independent, third-party checking behind the project's claims. It considers who audited the project, how thoroughly, and against which standard (for example Gold Standard or Verra). Weak or absent verification caps how much confidence any of the other dimensions can earn.
How the composite score is computed
The composite score is the equal-weighted average of the five dimension scores. Add the five numbers, divide by five, and you have a value from 0 to 100. That value maps to a letter grade.
| Grade | Composite score |
|---|---|
| AAA | 90 to 100 |
| AA | 80 to 89 |
| A | 70 to 79 |
| BBB | 60 to 69 |
| BB | 50 to 59 |
| B | 40 to 49 |
| CCC | 30 to 39 |
| D | below 30 |
Because the weighting is equal, a credit cannot hide a serious weakness behind one strong dimension. A project with excellent co-benefits but poor additionality will land in a middle band, which is the honest outcome.
What provisional means
A provisional assessment is one that has been drafted with real data and a real methodology but has not been confirmed by a qualified external verifier. It is a rigorous estimate, not a certified rating. Every grade currently on the platform is provisional, and the Provisional badge appears wherever a grade is shown.
What it takes to become verified
For an assessment to move from provisional to verified, a qualified external verifier (someone other than the platform operator) must confirm it and attach at least one evidence URL to every one of the five dimensions. Only then does the provisional marker come off.
During this phase, CarbSet has not yet onboarded such a verifier, so all assessments remain provisional. When the independent verification layer is live, confirmed assessments will lose the Provisional badge, and only those will be presented as verified.