How do I calculate the carbon footprint of a pair of socks?

Weigh the yarn in a pair, including knitting waste, and multiply by your spinner's per-kg figure. Add knitting, toe linking, dyeing or washing, boarding with steam, labels and packing, then divide the unit's energy by pairs passed.

Yarn

• Cotton, polyester, nylon and elastane by weight per pair.
• Ask the spinner for a per-kg yarn figure; blends differ.
• Knitting waste and rejected pairs.

Making

• Circular sock knitting machines and toe linking.
• Dyeing or washing, and boarding on heated forms.
• Pairing, labels, header cards and cartons.

Per pair

Report per pair by size and style, since an ankle sock and a knee-length sock carry very different yarn weights.

Worked example: sock unit per pair (one month)

• Electricity: 24,000 kWh x 0.710 = 17,040 kg CO2
• PNG: 2,000 SCM x 2.05 = 4,100 kg CO2
• Pairs passed: 300,000
• Plant total: 21,140 / 300,000 = 0.0705 kg CO2 per pair
• Add yarn per pair for the full figure

Inputs are illustrative; use your own bills and production records.

What Senseible does here

Senseible reads the plant's electricity bills (CEA grid factor 0.710 kg CO2 per kWh, CO2 Baseline Database version 21.0) and fuel invoices (IPCC 2006 defaults) into a fingerprinted Scope 1 and 2 record, the plant-level input to a per-unit figure. Bought-in materials go to the supplier evidence trail; product reports are self-declared drafts.

• Product carbon footprint calculator
• Knitted fabric footprint per kg
• Spinning mill footprint per kg of yarn
• Textile industry

Sources: GHG Protocol Product Standard, ISO 14067:2018, Carbon footprint of products (iso.org), IPCC 2006 Guidelines, Volume 2 Energy (fuel defaults), CEA CO2 Baseline Database, version 21.0

Last reviewed 2026-10-20.