What ISO 14067 actually requires
ISO 14067 defines a product carbon footprint (PCF) as the sum of greenhouse-gas emissions and removals attributable to a product across its life cycle, expressed in kg CO₂-equivalent per functional unit (e.g. per T-shirt, per kWh, per kg of cement).
It is built on the broader life cycle assessment standards ISO 14040 and ISO 14044 — same methodology, narrowed to one impact category (climate change).
The standard sets out six things you must document:
- Goal and scope — why the PCF exists and who it's for.
- Functional unit — what one unit of the product provides (e.g. "one 200 g cotton T-shirt").
- System boundary — which life-cycle stages are included.
- Inventory analysis — material and energy flows for each stage.
- Impact assessment — kg CO₂e using a recognised characterisation method (typically IPCC AR6 GWP100).
- Interpretation — data quality, assumptions, uncertainty.
Cradle-to-gate vs cradle-to-grave
The single biggest decision is the system boundary. Two choices dominate:
- Cradle-to-gate — from raw material extraction to the factory gate. Excludes distribution, use phase and end-of-life. Covers 80% of B2B supplier PCF requests (CSRD value-chain disclosures, CDP supplier questionnaires, CBAM).
- Cradle-to-grave — the full life cycle including transport to consumer, use and disposal. Required for environmental product declarations (EPDs), B2C labels, and Digital Product Passports.
If you don't know which one your buyer needs — ask. Most will say cradle-to-gate.
Emission factors: where the numbers come from
ISO 14067 requires that every emission factor used in the calculation is traceable, current, and appropriate for the geography and process. The standard does not mandate a specific database — what matters is that you cite your sources and that they are recognised. The most widely accepted include:
- DEFRA UK GHG Conversion Factors — annual, free, broadly used across Europe.
- US EPA GHG Emission Factors Hub — annual, free, US-focused.
- ADEME Base Empreinte (France) and UBA ProBas (Germany) — national equivalents.
- ecoinvent — the most comprehensive LCA database; paid licence required.
- Industry-specific datasets: worldsteel for steel, IAI for aluminium, PlasticsEurope for polymers.
Carbon Calculator's product footprint tool uses DEFRA, EPA, ADEME, UBA, PlasticsEurope, worldsteel and IAI factors for the underlying materials, and surfaces the source for every line item — that is the audit trail your buyer needs.
Do you need to be certified?
Almost certainly not. ISO 14067 distinguishes between three levels of assurance:
- Self-declared — the manufacturer publishes a PCF aligned with the standard. No external party involved. This is what 90% of supplier questionnaires accept.
- Critical review — an independent reviewer checks the calculation. Typical for B2B claims used in marketing.
- Third-party verification — a certification body (TÜV, SGS, Bureau Veritas) audits the PCF. Required for EPDs, public claims about reductions, and some regulated programmes.
Verification costs £5,000–£50,000+ and takes weeks. Most SMEs answering a CDP request, a sustainability rating questionnaire, or a buyer's RFP do not need it — they need a clear, defensible self-declared PCF they can send by Friday.
How Carbon Calculator helps
Our product carbon footprint calculator follows ISO 14067 principles:
- Explicit functional unit and boundary (cradle-to-gate in v1, cradle-to-grave coming).
- Every emission factor cites publisher, version and URL.
- The output PDF includes goal, scope, inventory and interpretation sections.
- We use the phrase "aligned with ISO 14067 principles" — never "ISO 14067 certified" — because we are not a certification body. If you need third-party verification, the audit trail we generate is exactly what an auditor will ask for.
Start with the free Quick mode to estimate a product in 30 seconds, or request access to the ISO-aligned mode for SME suppliers.