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Manifesto

What we believe.
What we won’t do.
Why it matters.

The personal carbon space is full of tools that prioritise your emotional comfort over accurate information. Decarb was built to do the opposite.

01

The problem with feeling good

The personal carbon market has sorted itself into two tonal modes. There is guilt — disaster imagery, the weight of individual responsibility pressing down on the user, a sense that you should already know how bad your footprint is. And there is optimism — gamification, feel-good offset badges, a gentle pat on the back for buying the slightly more expensive option.

Both modes share the same flaw. They prioritise emotional response over accuracy. They make the product easy to engage with by making the data easier to accept. The numbers are vague enough to be reassuring, the methodology buried deep enough that most users never check it.

The user Decarb is built for has already seen through this. They are not motivated by guilt and not satisfied by feel-good framing. They want accurate information — and tools honest enough to provide it.

That is a specific person. And almost no product in this space speaks to them directly.

02

Scientific integrity is not a brand attribute

Most companies in this space describe scientific credibility as a brand value. Something that sits alongside their tone of voice and colour palette. A reassuring signal in a crowded market.

At Decarb, it is a product requirement. The entire product — the calculator, the report, the methodology documentation, the content — is designed to answer one question before anything else: could a climate scientist read this and find nothing to dispute?

If the answer is no, it does not go out. That test applies to every emission factor we choose, every benchmark we reference, every claim in every blog post. It is the constraint that governs everything else.

Every emission factor has a named source. IPCC, EPA, eGRID, IEA, Poore & Nemecek, PCAF. Attributed inline, version-controlled, updated when better data becomes available.
Assumptions are visible, never buried. The methodology documentation is public. Every modelling decision is explained. No black-box coefficients.
Estimates are clearly labelled. We calculate estimated emissions, not verified emissions. The difference matters and we will always say so.
We will not use the words “carbon neutral” unless independently verified. Not for our own product. Not for partners. Not for anything we publish.
03

Measurement is the beginning, not the product

A carbon score is not useful on its own. Knowing you produce an estimated 14 tons CO₂e per year tells you almost nothing without context — what drives that number, how it compares to realistic benchmarks, and what you can actually do about it.

The Decarb report is built around the third question. The personal reduction plan — specific to your category breakdown, ranked by impact, grounded in sourced emission factors — is what the product is designed to deliver. The score is a starting point. The plan is the output.

This also shapes what we will never build: a dashboard that flatters your footprint by comparing you to the national average and leaving it there. Progress measured against a bad baseline is not progress worth measuring.

The right benchmark is the IPCC 1.5°C pathway — approximately 2.3 tons CO₂e per capita globally by 2030. We will always show you that number alongside your own.

04

Offsets are a last resort, not a solution

Decarb offers carbon offsets. We want to be clear about what that means and what it does not mean.

Offsetting is the act of funding emissions reductions elsewhere to compensate for emissions you cannot yet eliminate at source. Done through verified, high-quality projects, it is a legitimate tool. It is also frequently used to let people feel better about emissions they could have reduced directly, and to let companies make claims they cannot justify.

Decarb will only recommend offsets after a user has seen their reduction plan and understood where their estimated emissions actually come from.
We will not present offsetting as equivalent to reduction. It is not. The product copy, the report, and the offset page all say so explicitly.
We only offer offsets verified to credible standards. The project type, verification standard, and additionality assessment are disclosed for everything we list.
05

Individual action matters. We won’t pretend otherwise.

There is a well-rehearsed argument that personal carbon footprints are a distraction from systemic change — that the concept was popularised by oil companies to shift responsibility from industry to consumers, and that individual action has no meaningful impact on the climate.

There is real truth in the first part. The systemic failures of energy infrastructure, food systems, and transport policy cannot be solved by individual behaviour change alone. We do not dispute that.

But the conclusion — that individual action therefore does not matter — does not follow. Household energy use, diet, transport choices, and financial decisions collectively account for a significant share of global emissions. The same people making those choices vote, invest, and influence the institutions with the power to drive systemic change. The two are not in opposition.

Decarb was built on the belief that informed individuals make better decisions — and that the tools to support that should be held to the same standards as the institutions they engage with. That is the whole thesis.

06

We will tell you when we’re wrong

Emission factor science moves. New data supersedes old benchmarks. The eGRID grid factor we used in v1 has already been updated in v2 to reflect 2023 data. The EU banking emission intensity figure we currently use overstates actual financed emissions — we say so explicitly in the methodology and have flagged it for the next revision.

We will not quietly update numbers and pretend the old ones were always right. Every significant methodology change will be versioned, documented, and noted in the public methodology documentation. If a previous version of the calculator produced a number we now believe was wrong, we will say so.

Transparency about uncertainty is not a weakness. It is the only honest position in a field where the data is genuinely imperfect.

The test

Could a climate scientist read this and find nothing to dispute?

That is the question we ask before anything at Decarb goes out. It is a high bar. We do not always clear it on the first attempt. But it is the only bar worth measuring against — and it is the one we will keep holding ourselves to.

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