Open Plan A's product page and you'll see what a well-funded European SaaS company looks like in 2026. Clean dashboards. Tidy Scope 1/2/3 tiles. A "decarbonisation plan" wizard that actually works. Berlin-based, founded 2017, ISO 14064-certified methodology, Dax 40 logos in the footer. If you sat the product in front of a CFO who has never done carbon accounting, they would nod and approve the budget.
Open Formist and you'll see a chat window.
That's the gap this article is about. Plan A and Formist are both trying to solve corporate GHG reporting, and they've arrived at genuinely different answers to the same question: what should a carbon accounting tool feel like to use on a Tuesday afternoon when you have a utility bill, an HR export, and a supplier questionnaire sitting in your downloads folder?
What each one was built for
Plan A was built for the sustainability manager at a 300-to-3,000-person European company who has been told by the board — or by a German bank, or by a customer — that carbon accounting is now part of the job. The target persona is someone who wants a structured place to keep their data, a repeatable annual inventory, and a dashboard they can screenshot into a board deck. Plan A's bet is that this user wants software that looks like software: forms, tiles, filters, supplier portals, and an onboarding flow that guides them through their first Scope 1 calculation without a consultant in the room.
Formist, built by WeCarbon, is an AI-powered compliance platform that behaves like a knowledgeable colleague sitting next to you. You upload documents, describe what you need, and it fills out the forms. The target persona is different: someone who has already lived through one round of carbon accounting and realized that the bottleneck isn't the dashboard — it's the eight hours a week they spend copying numbers from PDFs into structured fields. Formist's bet is that this user would rather talk to something that can read than click through a wizard.
Neither bet is wrong. They're aimed at different people.
What they have in common
Before the differences, the overlap. Both products follow the GHG Protocol Corporate Standard for Scope 1, 2, and 3 inventories. Both maintain emission factor databases that are updated on a rolling basis — DEFRA, IEA, ecoinvent subsets for activity-based Scope 3, supplier-specific factors where they exist. Both produce outputs that will survive a limited-assurance pass from a reasonable auditor. Both offer supplier engagement flows, though the shape is different.
Both are also honest about the limits of the exercise. Neither will tell you that the market-based Scope 2 number you get from unbundled RECs is "real." Neither will let you claim a 90%-complete Scope 3 inventory when half your Category 1 spend is sitting in an uncategorized bucket. The methodology guardrails are roughly equivalent.
If your primary job is "build a defensible corporate GHG inventory and publish it once a year," either tool will get you there. The question is what the path looks like, and what else you need the tool to do.
Where Plan A wins
The dashboard. This is not a throwaway compliment. Plan A's dashboard is one of the best-looking and most usable carbon interfaces in the European market. Emissions are organized by scope, by category, by business unit, by period. Filters are fast. The decarbonisation planning module lets you model reduction scenarios against a baseline and see the SBTi-aligned trajectory overlay. If you need to show a board the story of your emissions — where they come from, how they've changed, what you plan to do about them — Plan A's default views are roughly what you would have built yourself if you had six months and a design team.
SME onboarding. If you've never done a GHG inventory before, Plan A walks you through it. The first-time flow is guided: here are your fuel invoices, here are your electricity meters, here is where you upload your employee commute survey, here is the supplier spend category dropdown. A sustainability manager with no prior training can get a first-draft inventory out of Plan A in a few weeks of part-time work. That's a real capability, and it's not easy to build.
EU references and trust. Plan A has Dax 40 clients. It has thousands of SMEs in Germany, France, and the Benelux. It's ISO 14064-certified in a way that German procurement departments like to see on tender responses. If your organization is European mid-market and your legal team is going to run a vendor risk assessment, Plan A will clear the bar with less friction than a younger platform. Founded-in-2017 matters to some buyers, and Plan A has earned that.
Carbon-only focus and depth. Because Plan A has stayed in the carbon accounting lane, its carbon features are deeper than a multi-framework tool's carbon features will be at any given moment. Supplier engagement modules, procurement analytics, country-specific emission factor nuances — these are mature in Plan A in a way that takes years to build.
Where Formist wins
The interaction model. This is the central difference. In Plan A, you fill forms. In Formist, you have a conversation and upload documents. The Formist agent reads your utility bill — in English, German, French, Chinese, or Arabic — extracts the kWh, identifies the country and supplier, applies the right emission factor, and places the value into the GHG inventory card. You review. You correct. You move on.
On any given week, the difference is measured in hours. A sustainability analyst at a mid-size manufacturer spends most of their "GHG time" not thinking — they spend it typing numbers out of PDFs into Plan A's (well-designed) forms. Formist eliminates that layer. Your job becomes reviewing extractions rather than performing them. Once you've done it for two weeks you can't go back.
Multi-framework coverage. Plan A is a carbon accounting tool. It does carbon well and it doesn't try to do much else. Formist handles CBAM, CSRD/ESRS, EU Taxonomy, CDP, ISSB, GHG Protocol, SBTi target-setting, LCA screening, and 15+ other frameworks under one subscription. The reason this matters is not the feature count — it's that the same datapoint feeds multiple frameworks, and nobody should be typing it in three times. Your FY2025 gross Scope 1 figure shows up in your GHG inventory, your CDP response, your CSRD E1 disclosure, your CBAM embedded-emissions calculation for in-scope products, and your SBTi progress report. Formist keeps it in one place. A carbon-only tool means a second subscription for CSRD, a third for CBAM, and a weekly reconciliation meeting.
Document ingestion over form-filling. Plan A can import data from connected systems — Xero, SAP, Google Sheets, a handful of ERPs. What it cannot do is take a PDF scan of a Chinese supplier's production data sheet, read it, extract the relevant figures, and place them in the right cells. Formist was built around that capability. For any company with suppliers outside Western Europe, this is not a marginal feature. It's the difference between "we'll include Scope 3 Category 1 next year" and "we have it now."
Geography. Both products serve EU customers well. Plan A is stronger on German and French SMEs; Formist has been deployed more heavily in Asia and the Middle East, with offices in Shanghai, Paris, and Dubai, and native document handling in Chinese, Arabic, and several other non-Latin-script languages. If your value chain stretches past Vienna, Formist has done more miles on that terrain.
Price, briefly
Neither company publishes a full price list, and inventing numbers for a comparison article is how this kind of piece loses credibility. What we can say, based on public reference points and what companies report in procurement forums: Plan A typically lands between €10,000 and €40,000 per year depending on company size, seats, and whether you take the decarbonisation planning modules. Formist is priced per workspace and per framework usage, and for a mid-size company doing carbon plus one or two adjacent frameworks (CSRD or CBAM) it generally comes in at or below the lower half of that range, with no additional license for the other frameworks. Get quotes from both and compare line by line — that's the only honest answer.
Which one to pick
Here is the actual recommendation, not a "it depends on your priorities" non-answer.
Pick Plan A if: your scope is carbon-only for the foreseeable future, you want a polished dashboard that a non-technical board will find legible, your team prefers forms and tiles to chat interfaces, and your value chain is predominantly European. Plan A is also the safer choice if you're doing your first GHG inventory ever and you want guided onboarding with a product that has thousands of SMEs already using it in a similar shape.
Pick Formist if: you're already past your first inventory and the pain is data entry, not methodology; you need more than carbon (CSRD, CBAM, CDP, ISSB all in the mix within the next 24 months); your supplier base includes Asia, Africa, or the Middle East and you receive documents in multiple languages; or you've noticed that your sustainability team spends most of its week typing rather than thinking, and you'd like that to change.
A reasonable hybrid, if you're genuinely torn: run a three-month pilot of Formist on a contained scope — one business unit's Scope 3 Category 1, say, or your CBAM quarterly filing — and keep Plan A on the corporate inventory. If Formist cuts the time by the margin that most users report, you'll have a decision on your hands within a quarter. If it doesn't, Plan A remains.
A footnote on switching
Switching from Plan A to Formist is not a data problem. Both tools export to structured formats — CSV, XLSX, JSON — and emission factor methodologies are transparent enough that a re-run of a prior year's inventory in a new tool will reconcile within a reasonable tolerance. The real switching cost is organizational: your team has built habits around one interaction model and changing to another is a behavioral shift, not a technical one. Budget two weeks of parallel running and one uncomfortable all-hands where you explain why the dashboard looks different now. That's the actual cost.
The carbon accounting market is going to keep bifurcating between polished dashboards and agent-style interfaces for another few years. Both models have a place. The question isn't which one is "right." It's which one your team will actually use at 4pm on a Wednesday when the deadline is Friday.
Formist is built by WeCarbon, a climate-tech company with offices in Paris, Shanghai, and Dubai. It handles GHG Protocol, CBAM, CSRD/ESRS, EU Taxonomy, CDP, ISSB, SBTi, LCA screening, and 15+ other sustainability frameworks in a single workspace.