CO2 Equivalent (GWP) Calculator
Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer
Last updated: July 26, 2026CO2 Equivalent (GWP) Calculator
Not all greenhouse gases warm the atmosphere equally per unit mass - Global Warming Potential (GWP) expresses how much more (or less) a gas contributes to warming compared to the same mass of CO2 over a set time horizon.
Formula: CO2e = mass × GWP
Example: 10 kg of a gas with a GWP of 28 (a commonly cited order-of-magnitude figure for methane over a 100-year horizon) produces 280 kg of CO2-equivalent warming impact.
How to Use This Calculator
- Enter the mass of gas released.
- Enter the gas's GWP factor for your chosen time horizon.
Important: GWP factors are periodically updated by international climate science bodies (such as the IPCC) and vary by the time horizon chosen (20-year vs. 100-year) - always use a current, authoritative GWP factor for the specific gas and time horizon your reporting requires, rather than assuming a single fixed value.