Estimate a household carbon footprint from electricity, natural gas, driving, and flying, then compare your annual tons of CO2e with the 16-ton US average.
Free toolNo signupFormula shown
Saved & recent
CHECK ENTRYSAVED
RESULT
—
FORMULA USEDCarbon Footprint Calculator
What this footprint covers
A carbon footprint adds up the greenhouse gases your activity releases, expressed as CO2-equivalent (CO2e). This calculator covers the four biggest household levers: electricity, natural gas, driving, and flying. Each is converted to pounds of CO2e with a standard factor, summed, and divided by 2,000 to reach short tons per year.
The four factors
Electricity: 0.85 lb CO2e per kWh, the US grid average — your monthly kWh times 12 times the factor. Natural gas: 11.7 lb per therm, the EPA combustion factor for methane. Driving: annual miles ÷ your mpg gives gallons, at 19.6 lb CO2e per gallon burned. Flying: about 1,100 lb CO2e per long round trip, roughly one transcontinental or transatlantic economy journey.
Reading your number
The US average sits near 16 tons per person per year, among the highest of any country; the global average is closer to 4.5. If your result is well above 16, energy and flights are the usual suspects; if it is far below, you are already outperforming most efficiency advice.
Worked example
A household uses 900 kWh of electricity and 40 therms of gas per month, drives 12,000 miles a year at 25 mpg, and takes 2 long flights.
Total 26,404 lb ÷ 2,000 = 13.2 tons CO2e — about 83% of the US average.
How to use it
Pull your monthly electricity (kWh) and gas (therms) from any utility bill.
Estimate annual miles and your real-world mpg.
Count long round-trip flights over the past year.
Compare your tons against the 16-ton US average in the sub-line.
Frequently asked questions
What is a carbon footprint?
It is the total greenhouse gas emissions caused by a person, household, or activity, converted into carbon-dioxide equivalents. It bundles CO2 plus stronger gases like methane into one comparable number.
How accurate is this carbon footprint calculator?
It is a solid screening estimate, not an audit. The four factors are national averages, so a home on a clean regional grid or an all-electric house will see real-world numbers drift from the estimate.
What units are used for carbon footprints?
Results appear in short tons of CO2e per year (2,000 lb per ton), the common US convention. One US ton equals about 0.91 metric tonnes, which is why global comparisons sometimes look slightly different.
Why is the US average 16 tons per person?
It reflects high electricity use, low vehicle fuel economy relative to other wealthy nations, natural gas heating, and frequent flying. The worldwide average is roughly 4.5 tons per person.
How can I reduce my carbon footprint?
The highest-leverage moves are flying less, driving fewer miles or switching to an efficient or electric vehicle, electrifying heat, and cutting household electricity. Small habit changes rarely move the total as much as those four.