Product Carbon Footprint refers to the total amount of direct and indirect greenhouse gases released by a product (or service) throughout its lifecycle. There are over a hundred known greenhouse gases, but carbon footprints of product typically include the six gases required to be reduced under the Kyoto Protocol: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCS), perfluorocarbons (PFCS), and sulfur hexafluoride (SF6).

The lifecycle of a product is often referred to as "from cradle to grave," encompassing the stages from raw material extraction and processing, to product manufacturing, packaging, marketing, use, reuse, and maintenance, all the way to recycling and final waste disposal. However, for many intermediate products, the product lifecycle is also often defined as "from cradle to gate," which includes the process from raw material extraction, through its own processing, to the product being delivered to downstream customers.