Vehicle Emissions Calculator

Calculate Your Car's CO2 Emissions Per Mile & Per Year — Gas, Diesel, Hybrid & EV Compared Using EPA Data

Calculate your vehicle's CO2 emissions per mile, per year, and vs. EPA averages. Compare gas, diesel, hybrid, and EV. Based on EPA MOVES4 data | Calculator4U

Calculate your vehicle's CO2 emissions and environmental impact.

About This Calculator

This vehicle emissions calculator estimates your car's CO2 output per mile, per year, and over its lifetime — based on your fuel economy (MPG), fuel type, and annual miles driven. Results use EPA MOVES4 model data and eGRID state grid carbon intensity figures to compare gasoline, diesel, hybrid, plug-in hybrid, and battery electric vehicles on a like-for-like basis.

Key emissions benchmarks (EPA data, 2024–2026):

  • Gasoline emissions per gallon burned: 8,887 grams CO2 (8.887 kg / 19.6 lbs). This is a fixed constant — it does not change by vehicle type or engine size. Only MPG changes the per-mile figure.
  • Diesel emissions per gallon burned: 10,180 grams CO2 (10.18 kg / 22.4 lbs). Diesel produces more CO2 per gallon, but higher fuel efficiency often keeps per-mile emissions competitive with gasoline.
  • Average US passenger vehicle: 404 g CO2/mile (22.0 MPG fleet average, EPA Green Vehicle Guide).
  • Average annual vehicle emissions: 4.6 metric tons CO2/year at 11,500 miles/year (EPA).
  • Average EV on US grid: ~1.13 metric tons CO2-equivalent/year including upstream electricity generation (EPA MOVES4) — approximately 75% less than the average gasoline vehicle.
  • EPA model year 2026 new vehicle standard: 161 g CO2/mile (equivalent to ~55 MPG if met by tailpipe reduction alone — CBO/C2ES).

Formula — CO2 per mile for any gasoline vehicle: 8,887 ÷ MPG = CO2 grams per mile. A 15 MPG pickup emits 592 g/mile. A 35 MPG sedan emits 254 g/mile. A 50 MPG hybrid emits 178 g/mile. Annual CO2 (metric tons) = (miles/year ÷ MPG) × 0.008887.

EV emissions vary by state. Battery electric vehicles produce zero tailpipe emissions but upstream grid emissions depend on your state's electricity mix. Lowest EV emission states: Washington (~30 g CO2/mile equivalent, hydropower grid), Vermont (~40 g/mile, nuclear and hydro), Oregon (~80 g/mile). Highest EV emission states: West Virginia (~290 g/mile, coal-heavy grid), Wyoming (~280 g/mile), Kentucky (~260 g/mile). Even in the most coal-heavy US grids, EVs produce lower lifecycle emissions than gasoline cars when manufacturing emissions are averaged over 10+ years of driving (MIT Mobility study, 2019; confirmed by DOE AFDC 2025 data). Select your state in the calculator to see your grid-specific EV emission rate.

2026 regulatory context: Transportation is the largest source of US greenhouse gas emissions, responsible for approximately 27–28% of total US CO2 output annually (EPA). Within transportation, passenger cars and light trucks produce about 57% of transportation emissions. The EPA model year 2026 new vehicle fleet standard is 161 g CO2/mile. Note: In February 2026, EPA repealed future GHG vehicle regulations beyond the MY2026 standard — NHTSA CAFE (fuel economy) standards remain in effect but no further emissions tightening is currently scheduled. Always check fueleconomy.gov for your specific vehicle's official EPA CO2 rating.

Frequently Asked Questions

How much CO2 does a car emit per mile?

The average US passenger vehicle emits approximately 404 grams of CO2 per mile (EPA, 22.0 MPG fleet average). Formula for any gasoline vehicle: CO2 g/mile = 8,887 ÷ MPG. Examples: 15 MPG SUV = 592 g/mile. 35 MPG sedan = 254 g/mile. 50 MPG hybrid = 178 g/mile. For diesel: 10,180 ÷ MPG. EVs produce zero tailpipe CO2 — but upstream grid emissions vary from ~30 g/mile (Washington, hydropower) to ~290 g/mile (West Virginia, coal-heavy grid).

How much CO2 does a car emit per year?

A typical US passenger vehicle emits approximately 4.6 metric tons of CO2 per year (EPA, 22.0 MPG, 11,500 miles/year). Formula: Annual CO2 (MT) = (miles/year ÷ MPG) × 0.008887. At 12,000 miles/year: 15 MPG pickup = 7.1 MT/yr. 25 MPG sedan = 4.3 MT/yr. 35 MPG car = 3.1 MT/yr. 50 MPG hybrid = 2.1 MT/yr. BEV on US average grid = ~1.13 MT CO2-eq/yr (EPA MOVES4). EVs produce approximately 75% less annual CO2 than the average gasoline vehicle.

Are electric vehicles (EVs) actually lower emissions than gas cars?

Yes — in virtually every US state, EVs produce lower lifetime emissions than comparable gasoline vehicles, even accounting for battery manufacturing and grid electricity. DOE: EVs average ~1.13 MT CO2-eq/year vs. ~4.29 MT for gasoline vehicles (EPA MOVES4, nationwide average grid). In clean-grid states like Washington, an EV emits up to 70% less CO2 over its lifetime. Even in coal-heavy grids, EVs outperform gasoline cars because electric motors are 3–4× more energy-efficient than combustion engines. Battery manufacturing adds ~12 MT CO2 (MIT) but EVs offset this within 2–3 years of average US driving.

How many grams of CO2 does a gallon of gasoline produce?

Burning one gallon of gasoline produces 8,887 grams of CO2 (19.6 lbs) — a fixed value set by gasoline's carbon content (EPA). Burning one gallon of diesel produces 10,180 grams CO2 (22.4 lbs). Most of the CO2 weight comes from oxygen in the air — which is why a ~6-pound gallon of gasoline produces nearly 20 pounds of CO2. The standard US E10 blend (10% ethanol) produces a similar per-mile figure because ethanol has lower carbon but also lower energy content per gallon.

What is the EPA vehicle emissions standard for 2026?

The EPA model year 2026 fleet-wide GHG standard for new light-duty vehicles is 161 g CO2/mile — equivalent to ~55 MPG if met by tailpipe reduction alone (CBO/C2ES). This applies to new vehicles only; the average car currently on US roads emits ~404 g CO2/mile. Note: In February 2026, EPA repealed GHG vehicle regulations beyond MY2026 — no further tailpipe emissions tightening is currently scheduled. NHTSA CAFE (fuel economy) standards remain in effect.

How do I calculate my vehicle's carbon footprint?

For a gasoline vehicle: Annual CO2 (metric tons) = (miles/year ÷ MPG) × 0.008887. Example: 12,000 miles/year at 28 MPG = (12,000 ÷ 28) × 0.008887 = 3.8 MT CO2/year. Find your EPA MPG at fueleconomy.gov or calculate from fill-ups. For an EV: look up your state's grid carbon intensity from EPA eGRID, multiply by annual kWh usage, convert to metric tons. Or use the Calculator4U vehicle emissions calculator to get instant results with state-specific EV comparisons.

How do vehicle emissions vary by state for EVs?

EV emissions vary by state based on the electricity grid mix (EPA eGRID). Lowest-emission EV states: Washington (~30 g CO2/mile equivalent, hydropower), Vermont (~40 g/mile, nuclear/hydro), Oregon (~80 g/mile). Highest-emission EV states: West Virginia (~290 g/mile, coal), Wyoming (~280 g/mile), Kentucky (~260 g/mile). The US average EV rate is approximately 200 g CO2/mile equivalent — about half the average gasoline car's tailpipe emissions alone. EVs are carbon-positive in every US state when the full lifecycle is compared to gasoline vehicles.

How does transportation contribute to US CO2 emissions?

Transportation is the largest single source of US greenhouse gas emissions — approximately 27–28% of total US CO2 output annually (EPA). Breakdown within transportation: passenger cars and light trucks ~57% (~15.6% of all US emissions); medium and heavy-duty trucks ~23%; aviation ~8%; rail ~2%. Reducing personal vehicle emissions is the highest-impact action available to most US households — more impactful than diet changes, home energy efficiency, or flight reduction for the average American driving 11,500+ miles per year.