CO2 Emissions per Mile/km Calculator
Calculate CO2 emissions per mile or kilometer by vehicle type and fuel type.
Understand your carbon footprint from driving.
Carbon emissions from transportation are calculated by combining fuel consumption with emissions factors — the mass of CO2 released per unit of fuel burned.
Core driving formula:
CO2 per mile = CO2 per gallon / Fuel Economy (MPG)
Total CO2 = Distance × CO2 per mile
CO2 emissions factors by fuel type:
| Fuel | CO2 per gallon | CO2 per liter |
|---|---|---|
| Gasoline | 8,887 g (19.6 lbs) | 2,348 g |
| Diesel | 10,180 g (22.4 lbs) | 2,689 g |
| E85 Ethanol blend | ~6,500 g (14.3 lbs) | ~1,717 g |
Diesel produces more CO2 per gallon, but diesel engines typically achieve 20–30% better fuel economy, making the per-mile emissions comparable.
Average CO2 per mile by vehicle type (US):
| Vehicle | Avg Fuel Economy | CO2 g/mile | CO2 lbs/mile |
|---|---|---|---|
| Compact car | 33 MPG | 269 g | 0.59 lbs |
| Midsize sedan | 28 MPG | 317 g | 0.70 lbs |
| SUV (midsize) | 22 MPG | 404 g | 0.89 lbs |
| Pickup truck | 18 MPG | 494 g | 1.09 lbs |
| Minivan | 24 MPG | 370 g | 0.82 lbs |
| Hybrid (avg) | 48 MPG | 185 g | 0.41 lbs |
| Electric (US grid avg) | — | ~120 g | ~0.26 lbs |
Worked example: A commuter drives 12,000 miles per year in an SUV averaging 22 MPG. CO2 per mile = 8,887 / 22 = 404 g/mile Annual CO2 = 12,000 × 404 = 4,848 kg (10,686 lbs) That is nearly 5 metric tons of CO2 per year — just from commuting.
Putting it in perspective:
- The average American generates ~16 metric tons of CO2 per year (all sources)
- Transportation accounts for ~27% of US greenhouse gas emissions
- Each gallon of gasoline not burned saves about 19.6 lbs of CO2
- Carpooling with one other person immediately halves your per-person emissions
Electric vehicle note: Electric vehicle emissions vary dramatically by electricity source. Coal-heavy grids may produce 250+ g CO2/mile equivalent. Renewable-powered regions (Pacific Northwest, Iceland) drop below 30 g/mile.