{
  "slug": "carbon-footprint-drive",
  "title": "Driving Carbon Footprint Calculator",
  "heading": "Driving Carbon Footprint Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/carbon-footprint-drive",
  "summary": "Estimate CO2 emissions from a car trip based on distance, fuel economy, and fuel type.",
  "description": "Every gallon of gasoline burned releases about 8.887 kg of CO2, and diesel releases slightly more at 10.18 kg per gallon due to its higher carbon density, regardless of engine efficiency — efficiency only changes how many gallons you burn to cover a given distance. This calculator converts your trip distance and fuel economy into gallons consumed, then applies EPA emission factors to get total CO2. For electric vehicles it instead uses your electricity consumption rate and local grid carbon intensity, which varies enormously by region — a Prius on a coal-heavy grid can emit comparably to an EV on that same grid, which is why 'EVs are zero-emission' is only true at the tailpipe, not the power plant.",
  "formula": "Gas/diesel: gallons = miles ÷ MPG; CO2 = gallons × factor (8.887 kg/gal gas, 10.18 kg/gal diesel). EV: CO2 = (miles ÷ miles-per-kWh) × grid intensity.",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=carbon-footprint-drive",
  "inputs": [
    {
      "id": "fuelType",
      "label": "Fuel type",
      "kind": "select",
      "hint": null,
      "default": "gas",
      "options": [
        {
          "value": "gas",
          "label": "Gasoline"
        },
        {
          "value": "diesel",
          "label": "Diesel"
        },
        {
          "value": "ev",
          "label": "Electric"
        }
      ]
    },
    {
      "id": "distance",
      "label": "Trip distance",
      "kind": "number",
      "hint": null,
      "default": 300,
      "unit": "miles",
      "min": 1,
      "max": null
    },
    {
      "id": "mpg",
      "label": "Fuel economy (MPG or mi/kWh)",
      "kind": "number",
      "hint": null,
      "default": 28,
      "unit": null,
      "min": 1,
      "max": null
    },
    {
      "id": "gridIntensity",
      "label": "Grid carbon intensity (EV only)",
      "kind": "number",
      "hint": null,
      "default": 0.37,
      "unit": "kg CO2/kWh",
      "min": 0,
      "max": 1
    }
  ],
  "outputs": [
    {
      "id": "totalKg",
      "label": "Total CO2 emissions (kg)",
      "format": "number",
      "hint": null,
      "primary": true
    },
    {
      "id": "unitsUsed",
      "label": "Fuel/electricity used (gal or kWh)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "perMile",
      "label": "CO2 per mile (kg)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "tonnes",
      "label": "Total (metric tonnes)",
      "format": "decimal",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Fuel type: Gasoline",
      "Trip distance: 300 miles",
      "Fuel economy (MPG or mi/kWh): 28",
      "Grid carbon intensity (EV only): 0.37 kg CO2/kWh"
    ],
    "outputs": [
      "Total CO2 emissions (kg): 95.2",
      "Fuel/electricity used (gal or kWh): 10.71",
      "CO2 per mile (kg): 0.317",
      "Total (metric tonnes): 0.095"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter fuel type.",
      "Enter trip distance (miles).",
      "Enter fuel economy (mpg or mi/kwh).",
      "Enter grid carbon intensity (ev only) (kg CO2/kWh).",
      "Read your total co2 emissions (kg) on the right — it updates as you type.",
      "Hit Share to keep the scenario or send it to someone."
    ]
  },
  "scenarios": [
    {
      "name": "Conservative",
      "description": "Lower-end numbers — what if things land soft?",
      "values": {
        "fuelType": "gas",
        "distance": 180,
        "mpg": 17,
        "gridIntensity": 0.222
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "fuelType": "gas",
        "distance": 300,
        "mpg": 28,
        "gridIntensity": 0.37
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "fuelType": "gas",
        "distance": 480,
        "mpg": 45,
        "gridIntensity": 0.592
      }
    }
  ],
  "limitations": [
    "Estimates assume standard, average conditions — local rules, pricing, and materials vary.",
    "Results are rounded for readability; add a buffer before ordering, booking, or committing.",
    "Double-check anything with a real cost attached against a local quote."
  ],
  "faq": [
    {
      "q": "Why does diesel emit more CO2 per gallon than gasoline if it's more efficient?",
      "a": "Diesel is denser and contains more carbon atoms per gallon than gasoline, so it emits more CO2 per gallon burned. Diesel engines are typically 20-30% more fuel-efficient though, so the total trip emissions often still come out lower or comparable overall."
    },
    {
      "q": "How do I find my region's grid carbon intensity for the EV calculation?",
      "a": "The EPA's eGRID data and the EIA publish average CO2 intensity by region and utility; it ranges from under 0.1 kg CO2/kWh in hydro-and-nuclear-heavy grids like the Pacific Northwest to over 0.7 kg CO2/kWh in coal-dependent grids, roughly a 7x spread."
    },
    {
      "q": "Is an EV always lower-carbon than a gas car?",
      "a": "In almost every US grid region, yes, over the vehicle's driving lifetime, even accounting for battery manufacturing emissions, but the margin varies a lot — an EV on a very clean grid can be 3-5x lower carbon per mile than gas, while on a coal-heavy grid the advantage shrinks closer to 1.5-2x."
    },
    {
      "q": "Does this account for manufacturing emissions?",
      "a": "No, this calculator is use-phase only (fuel burned or electricity consumed for driving). EVs have higher upfront manufacturing emissions from battery production, which studies show is typically offset within 1-2 years of average driving compared to a similar gas vehicle."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/carbon-footprint-flight",
    "https://www.revenuelab.fyi/toolbox/carbon-footprint-home",
    "https://www.revenuelab.fyi/toolbox/tree-carbon-offset"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Driving Carbon Footprint Calculator (https://www.revenuelab.fyi/toolbox/carbon-footprint-drive)"
}