Free Carbon Footprint Calculator
Estimate your annual carbon footprint from electricity, gas, and driving. See total CO2 emissions in metric tons per year.
kWh
therms
miles
mpg
Total Annual CO2
11.96 metric tons
Electricity CO24.51 metric tons
Natural Gas CO23.18 metric tons
Driving CO24.27 metric tons
Total Annual CO2 vs Monthly Electricity Use
How to Calculate Your Carbon Footprint
Your carbon footprint is the total greenhouse gas emissions from your activities, measured in metric tons of CO2 per year.
Key Emission Factors
Formula
Total CO2 (metric tons) = (Electricity CO2 + Gas CO2 + Driving CO2) / 2204.6
Each source is computed from usage multiplied by its emission factor, then converted from pounds to metric tons.
Example Calculation
A household uses 900 kWh of electricity per month, 50 therms of gas per month, and drives 12,000 miles per year in a 25 mpg vehicle.
- 01Electricity CO2: 900 * 12 * 0.92 = 9,936 lbs = 4.51 metric tons
- 02Natural Gas CO2: 50 * 12 * 11.7 = 7,020 lbs = 3.18 metric tons
- 03Driving CO2: (12000 / 25) * 19.6 = 9,408 lbs = 4.27 metric tons
- 04Total: 4.51 + 3.18 + 4.27 = 11.96 metric tons CO2/year