Declared carbon footprints

A product carbon footprint is the quantity of greenhouse gases, in kilograms of CO2 equivalent (kg CO2e), attributed to one unit of a product, such as one kilogram of green coffee. It is calculated by someone who has the data and the method: your company's sustainability team, a consultant, a supplier, or a footprint tool.

A-REX does not calculate footprints. It keeps the footprint someone else calculated, with the name of who published it, who calculated it, and whether an independent third party verified it.

Where a footprint can go

• On a product: in Products, select Declare carbon footprint in the row menu. Every lot of the product shows it as "declared for the product, not specific to this lot".
• On a lot: on the lot page, in Passport and carbon footprint, select Declare footprint. It becomes part of the lot's information once someone approves it, like a correction. The lot's own footprint replaces the product's on that lot.

Read a PACT file

Footprint tools and suppliers that follow the WBCSD PACT Technical Specifications 3.x export a "ProductFootprint" file. Drag it into Read a PACT file: the value, the declared unit, the reference period, who published it, the methodology and the verification fill the form. Check them, complete what is missing, and send. Without a file, type the values from the issuer's report.

What is required

• The value in kg CO2e and the declared unit it refers to (for example per 1 kilogram).
• The reference period the data covers.
• Who published the footprint, and its id in their file or report.
• The methodology, such as ISO 14067 or the GHG Protocol Product Standard.
• Whether a third party verified it. A verified footprint names who verified it; a footprint nobody verified is shown as Not verified.

What A-REX never does

• It never calculates, converts or adds up footprints. A lot made from several lots does not get the sum of their footprints: under mass balance, a lot's footprint cannot be traced to specific inputs, so whoever calculated it declares one for that lot.
• It never subtracts carbon credits from a footprint. Credits set aside for a lot are shown apart.
• It never writes "carbon neutral", "climate positive", "net zero" or similar claims, and refuses them in a footprint's text: EU rules on environmental claims (Directive (EU) 2024/825) restrict them.

Change or remove a footprint

On a product, open Declare carbon footprint again to change it, or select Remove footprint. On a lot, select Replace footprint or Remove footprint: each is approved like a correction, and the earlier version stays on record. See Correct a lot's information.

All declared footprints in one report

The Declared footprint register in Reports › Catalog › Sustainability lists every footprint declared for your products and lots, exactly as declared: who declared it, the value per declared unit, the reference period and who verified it. It never adds them up. As JSON, it is the list of PACT product footprints. See Footprints your suppliers declared.