Vehicle Emissions Estimator
Estimate your vehicle's annual CO₂ emissions based on fuel type, fuel efficiency, and annual mileage.
Formulas Used
Gasoline / Diesel / E85:
CO₂ (lbs/year) = (Annual Miles ÷ MPG) × Emission Factor (lbs CO₂/gallon)
CO₂ (kg/year) = CO₂ (lbs/year) × 0.453592
CO₂ (metric tons/year) = CO₂ (kg/year) ÷ 1000
CNG:
CO₂ (lbs/year) = (Annual Miles ÷ MPGe) × 11.47 lbs CO₂/gallon-equivalent
Electric:
Energy (kWh/year) = Annual Miles × (kWh per 100 mi ÷ 100)
CO₂ (lbs/year) = Energy (kWh/year) × Grid Emission Factor (lbs CO₂/kWh)
Emission Factors (EPA):
Gasoline: 19.59 lbs CO₂/gallon | Diesel: 22.46 lbs CO₂/gallon |
E85: 12.73 lbs CO₂/gallon | CNG: 11.47 lbs CO₂/gallon-equivalent
Assumptions & References
- Emission factors sourced from the U.S. EPA — "Emission Factors for Greenhouse Gas Inventories" (2023).
- Gasoline CO₂ factor: 19.59 lbs CO₂/gallon (includes combustion only, not upstream).
- Diesel CO₂ factor: 22.46 lbs CO₂/gallon.
- E85 CO₂ factor: 12.73 lbs CO₂/gallon (net, accounting for ethanol bio-carbon).
- CNG CO₂ factor: 11.47 lbs CO₂/gallon-equivalent.
- U.S. average grid emission factor: 0.386 lbs CO₂/kWh (EPA eGRID 2023 national average).
- Calculations reflect tailpipe (tank-to-wheel) CO₂ only; upstream (well-to-tank) emissions are excluded unless noted.
- Average U.S. driver travels approximately 14,263 miles/year (FHWA 2022).
- 1 metric ton = 1,000 kg = 2,204.62 lbs.