There are many carbon accounting platforms, and their marketing all sounds similar. Instead of a ranking (which would be marketing too), here's how to evaluate them, written from the perspective of someone who understands how they work under the hood.
Evaluation criteria
| Criterion | Questions to ask |
|---|---|
| Methodology | GHG Protocol-aligned? Location and market-based Scope 2? |
| Emission factors | Which sources and versions? Can you see the factor used per line? |
| Scope 3 | Which of the 15 categories? Spend, activity, and supplier-specific methods? (Scope 3 data) |
| Integrations | ERP, accounting, travel, energy, and utility data? |
| Audit trail | Can every number be traced to source data? |
| Reporting | CSRD/ESRS, CDP, SBTi, national schemes? (CSRD pipelines) |
| Supplier engagement | Portals or data requests for suppliers? |
| Data export | Can you get your data out in a usable format? |
| Pricing | Per entity, per user, per module? |
Platforms commonly shortlisted
Enterprise and mid-market buyers often compare platforms such as Watershed, Persefoni, Sweep, Greenly, Normative, and Plan A, plus modules from Microsoft and Salesforce for organisations already on those ecosystems. SMEs often start with lighter tools or spreadsheets.
Ask each for a demo with your own data, not their sample data.
Red flags
- Black-box factors you can't inspect
- No audit trail
- Glossy dashboards, weak data import
- Locked-in data with no export
- "Net zero" claims built into the product without methodology
Build vs buy
For most companies, buy. Build only if carbon data is core to your product. The data model is simple, but factor management, Scope 3 methods, and audit requirements are not.