Carbon Footprint Calculator
Carbon Footprint Calculator works out Total annual footprint and Per person from Electricity used a year, Electricity grid and Supplier-specific factor. The default figures on this page give total annual footprint of 3.671505 t CO2e; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
3 steps
- Electricity: 10500 kWh x 0.3496671006 kg CO2e/kWh = 3671.5 kg CO2e
- Total 3671.5 kg CO2e, or 3.672 tonnes a year.
- All factors are on the IPCC AR5, 100-year, without climate-carbon feedbacks basis.
Breakdown by sourcetable
| source | amount | unit | kgCO2e | sharePercent | factor |
|---|---|---|---|---|---|
| Electricity | 10,500 | kWh | 3,671.505 | 100 | 0.3496671006 kg CO2e/kWh |
Factors appliedtable
| item | factor | unit | source |
|---|---|---|---|
| Electricity (United States national average) | 0.349667 | kg CO2e/kWh | US EPA eGRID2023 data file revision 2 (2025-06-12), sheet SRL23/US23, annual total-output emission rates. Cross-check: the 2025 EPA GHG Emis |
Figures from greenhouse gas emission factors, checked 31 August 2026. Its 5 worked examples are re-run on every release, last on 15 September 2026. What changed · how reference data is kept current
Sources and references
4 sources
What the Carbon Footprint Calculator calculates
Estimates an annual greenhouse gas footprint from household electricity, heating fuel, vehicle fuel and flights, using published emission factors.
How to use this Carbon Footprint Calculator
Enter Electricity used a year, Electricity grid, Supplier-specific factor and Heating fuel. Total annual footprint updates as you type, and “Use a worked example” loads checked figures you can adjust. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Total annual footprint, Per person and Electricity.
The method follows US EPA, Greenhouse Gas Emission Factors Hub, US EPA eGRID, annual total-output emission rates, UK DESNZ, Greenhouse gas reporting: conversion factors and IPCC Fifth Assessment Report, 100-year global warming potentials.
10,000 kWh on the US average grid example
With Electricity used a year: 10000, Electricity grid: US_AVERAGE, the calculator returns Electricity: 3496.671006. This example is checked against an independent source in the test suite.
What you can compare
Change one input at a time to see how it affects Total annual footprint, Per person and Electricity. The inputs you can vary are Electricity used a year, Electricity grid, Supplier-specific factor, Heating fuel, Heating fuel used a year and Vehicle fuel.
Understanding Total annual footprint, Per person and Electricity
An estimate built from published average factors. A reported inventory needs supplier-specific and activity-specific data, and should follow the GHG Protocol.
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
See something wrong? Report a problem with this calculator
Frequently asked questions
Is there a carbon footprint calculator?
Estimates an annual greenhouse gas footprint from household electricity, heating fuel, vehicle fuel and flights, using published emission factors. On the figures this page opens with — electricity used a year 10,000 kWh — the total annual footprint is 3.671505 t CO2e. Put your own figures in their place and the working updates beside the result.
How do I calculate my carbon footprint?
Estimates an annual greenhouse gas footprint from household electricity, heating fuel, vehicle fuel and flights, using published emission factors. Open “How this is worked out” beside the result to see each step for your own figures.
What are the best carbon footprint calculators?
Estimates an annual greenhouse gas footprint from household electricity, heating fuel, vehicle fuel and flights, using published emission factors. On this page it is computed from Electricity used a year, Electricity grid and Supplier-specific factor and shown as Total annual footprint, Per person and Electricity.
Is there a food footprint calculator?
It needs Electricity used a year, Electricity grid, Supplier-specific factor, Heating fuel, Heating fuel used a year and Vehicle fuel. Nothing else is required, and the figures stay in your browser.
What is the best app for calculating my carbon footprint?
The result gives Total annual footprint, Per person, Electricity, Heating fuel, Vehicle fuel and Flights, each labelled with its unit so the figure can be read on its own.
What information do I need for the Carbon Footprint Calculator?
You need Electricity used a year, Electricity grid, Supplier-specific factor, Heating fuel, Heating fuel used a year, Vehicle fuel, Vehicle fuel used a year and Distance driven a year. The page opens with default figures that give total annual footprint of 3.671505 t CO2e, so you can see the scale before entering your own.