A plain-English explainer from the Repricing Carbon series. New here? Start with What Is a Carbon Credit?
“High quality” sounds like a vibe. It is not. When experts say a carbon credit is high quality, they mean it holds up against five specific questions. Most credits in circulation fail at least one of them. Once you know the five, you can read past the marketing on almost any project. Here they are, in plain English.
1. Additionality: would this have happened anyway?
This is the big one. A credit is only real if the climate action would not have happened without the money from selling credits. If a forest was never going to be cut down, paying to “protect” it changes nothing, and the credit is empty. Additionality asks a blunt question: did your money actually cause the carbon savings, or are you paying for something that was going to happen regardless?
2. Baseline: compared to what?
Every credit is measured against a “what would have happened otherwise” scenario, called the baseline. A project claims it saved carbon compared to that scenario. The trouble is that the baseline is a prediction, and predictions can be inflated. If a project assumes a wildly pessimistic future (“this entire forest would have been clear-cut”), it can claim huge savings that were never really at risk. A credible baseline is realistic. An inflated baseline manufactures credits out of thin air.
Additionality and baseline are cousins. One asks whether the action needed your money. The other asks whether the claimed savings were honestly measured.
3. Permanence: will it stay put?
Carbon dioxide lasts in the atmosphere for centuries. So a credit only counts if the carbon it saved stays saved. A forest planted today can burn down in ten years and release everything right back. Carbon pumped underground is meant to stay for good. Permanence asks how long the climate benefit will actually last, and what happens if it reverses. The longer and more secure, the better.
4. Leakage: did the problem just move?
Leakage is the sneaky one. Imagine a project protects one forest, and the loggers simply move next door and cut down a different one. The carbon was not saved. It just relocated. Leakage asks whether a project pushed the emissions somewhere else instead of preventing them. A good project measures and accounts for this. A weak one ignores it and counts savings that did not really occur.
5. MRV: can you actually prove it?
MRV stands for Monitoring, Reporting, and Verification. It is a technical-sounding term for a simple idea: can the project show its work? Is someone measuring the carbon over time, reporting it honestly, and getting it checked by an independent party? Strong MRV means the claims are backed by real, ongoing evidence. Weak MRV means you are taking the project’s word for it.
The five in one breath: Did the money cause it (additionality)? Was the comparison honest (baseline)? Will it last (permanence)? Did the problem just move (leakage)? Can they prove it (MRV)?
Why this matters for a buyer
You do not need to run these tests yourself. That would take a team of specialists and weeks per project. The point of knowing the five questions is that you can now understand what a serious assessment is actually measuring, and you can tell when a project is dodging one of them.
This is exactly the work an independent rating firm does at scale. A company like Calyx Global runs each credit through questions like these and turns the answers into a score a buyer can act on. Knowing the five questions is how you read a rating with open eyes instead of just trusting a number.
Where to go next
That is the anatomy of quality. Five questions, and most credits stumble on at least one. If you want the deeper version, with examples of how real projects pass and fail each test, that is Part 2 of the series. And once you understand the questions, the natural next step is learning who answers them for you, which is what a carbon rating is.
Carbon Credit 101 · Step 3 of 5
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A note from the author. I am a writer who cares about sustainability, and when it comes to carbon credits I am still very much a learner. There are a lot of people who know this market far better than I do, and I have real respect for the work they have put into building it. If I got something wrong in here, I apologize, and I would genuinely like to hear about it so I can learn and correct it. I am writing this to start a conversation, not to have the last word. That is the whole point. This is a learning experience for me too, and the conversation is what moves all of us forward. If this piece helped you, share it. If you see it differently, even better. Let’s talk.