What Is a Carbon Footprint?
A carbon footprint is the total amount of greenhouse gases released into the atmosphere as a result of an activity, product, service, or lifestyle. It is measured in kilograms or tonnes of carbon dioxide equivalent, written as kg CO2e. The “equivalent” part matters because it accounts for other greenhouse gases like methane and nitrous oxide, converted to the warming impact of CO2.
What Is a Product Carbon Footprint?
A product carbon footprint tracks the emissions tied to a single item or service across its entire life. This includes five main stages: extracting and processing raw materials, manufacturing the product, transporting it to stores or the buyer, the energy used while it is owned and used, and what happens when it is disposed of or recycled. Each stage contributes a share of the total footprint, though the balance varies widely by product or service. A cotton t-shirt, for example, generates most of its emissions during raw material production and consumer washing, while a laptop’s biggest share comes from manufacturing.
Note: CarbonGuru provides scientifically and economically driven carbon analysis for purchasers across all these lifecycle stages, covering goods, services, and activities. While the five-stage lifecycle model is the standard framework used in environmental science, CarbonGuru’s analysis captures the full production and distribution impact so you do not need to calculate each stage yourself.
How Is It Measured?
Researchers use data from supply chains, energy grids, transportation networks, and waste systems to estimate emissions at each stage. International standards like ISO 14067 guide the process so that footprints from different products and services can be compared fairly.
Why It Matters for Purchasers
When you know the carbon footprint of what you buy โ whether you are an individual consumer, a procurement team, or a business purchasing supplies and services โ you can make more informed choices. Comparing two similar products or services by their footprint is like comparing price tags, except this tag shows the climate cost. Over time, attention to these numbers from both individual and business buyers encourages companies to reduce emissions throughout their supply chains.