Calculate weighted recycled content across packaging components

Define the purchasing question

Recycled content across a complete pack is a mass-weighted balance, not the average of the component percentages.

Use the result for transparent arithmetic over the entered components. Confirm the relevant claim boundary and evidence before making an environmental or regulatory statement.

Collect measurements that match the calculation

Obtain verified recycled fractions and measured masses for every included component. Define whether labels, closures, liners and adhesives are in scope; retain supplier evidence and dates.

Weight supplier-verified fractions by actual component mass. Unknown content is not confirmed zero; obtain evidence and define the included component scope before using a result in a claim.

• Component A mass (g)
• Verified recycled percentage A (%)
• Component B mass (g)
• Verified recycled percentage B (%)
• Component C mass (g)
• Verified recycled percentage C (%)

Work through an illustrative case

Weighted percentage = Σ(Mass × Recycled percentage)/Σ(Mass)

6 g recycled material in 26 g total equals 23.08%.

Replace these illustrative inputs with measured data or a quotation for the same scope. Change one assumption at a time so that a difference can be traced to a dimension, quantity, charge or process change.

Avoid the expensive comparison error

Two components at 100% and 0% do not necessarily give 50% overall. Unknown content is not evidence of zero or of compliance with any specific rule.

• Arithmetic mass balance, not certified compliance.
• Only entered components are included; retain supplier evidence and scope.

Common questions