Car (Petrol)
Car (Diesel)
Electric Car (grid mix)
Motorcycle
Bus
Train
Flight (Short Haul < 1000km)
Flight (Medium Haul 1000-3500km)
Flight (Long Haul > 3500km)
Estimated CO2 Emissions
— kg CO2
per trip
Understanding CO2 Emissions from Transportation
Calculating the carbon dioxide (CO2) emissions generated by transportation is crucial for understanding our environmental impact and making informed decisions. This calculator estimates CO2 emissions based on the mode of transport, the distance traveled, and the number of passengers.
How it Works: The Math Behind the Calculator
The core of this calculator relies on average CO2 emission factors per passenger-kilometer (or per kilometer for single-occupancy modes) for various transportation types. These factors are approximations derived from studies and databases that track the greenhouse gas output of different vehicles and travel methods.
The general formula used is:
Estimated CO2 Emissions = (Emission Factor per km) * (Distance Traveled in km) / (Number of Passengers)
For modes where the emission factor is already per passenger-km (like flights), the division by the number of passengers might be implicitly handled by the factor itself or adjusted. For simplicity and clarity in this calculator, we apply the division by passengers to all modes to show per-person impact where applicable.
Emission Factors (Approximate, kg CO2 per km):
Car (Petrol): ~0.18 – 0.25 kg CO2/km (varies greatly by car efficiency)
Car (Diesel): ~0.17 – 0.22 kg CO2/km (generally slightly more efficient than petrol)
Electric Car (grid mix): ~0.05 – 0.10 kg CO2/km (depends heavily on the electricity generation source)
Motorcycle: ~0.08 – 0.12 kg CO2/km
Bus: ~0.10 – 0.15 kg CO2/km (can be lower per passenger if full)
Train: ~0.02 – 0.05 kg CO2/km (electric trains are often very low)
Flight (Medium Haul 1000-3500km): ~0.18 – 0.22 kg CO2/km
Flight (Long Haul > 3500km): ~0.16 – 0.20 kg CO2/km
Note: These factors are illustrative. Actual emissions can vary significantly due to vehicle age, fuel efficiency, driving style, load, specific grid energy mix, and flight altitude. Emission factors for flights often include an uplift factor to account for non-CO2 warming effects at altitude.
Use Cases for this Calculator:
Personal Awareness: Understand the carbon footprint of your daily commute, travel, or specific journeys.
Travel Planning: Compare the CO2 impact of different travel options (e.g., train vs. flying vs. driving) for a vacation or business trip.
Education: Teach about the environmental impact of various transportation methods.
Corporate Sustainability: Businesses can use such tools to estimate the emissions from employee travel and identify areas for reduction.
Policy Advocacy: Provide data to support arguments for sustainable transportation initiatives.
By using this calculator, you take a step towards understanding and potentially reducing your contribution to greenhouse gas emissions.
function calculateCO2() {
var selectedMode = document.getElementById("transportationMode").value;
var distance = parseFloat(document.getElementById("distance").value);
var passengers = parseInt(document.getElementById("passengers").value);
var emissionFactorPerKm = 0;
var resultUnit = "per trip";
// Default emission factors in kg CO2 per kilometer
// These are simplified averages and can vary greatly in reality.
var factors = {
"car_petrol": 0.19, // Approx. 150g CO2/km * 1.25 efficiency factor
"car_diesel": 0.18, // Approx. 130g CO2/km * 1.35 efficiency factor
"electric_car": 0.07, // Highly variable, depends on grid mix
"motorcycle": 0.10,
"bus": 0.12, // Average, lower per passenger when full
"train": 0.03, // Very low for electric trains
"flight_short": 0.22, // Includes radiative forcing adjustment
"flight_medium": 0.20,
"flight_long": 0.18
};
if (factors.hasOwnProperty(selectedMode)) {
emissionFactorPerKm = factors[selectedMode];
} else {
alert("Invalid transportation mode selected.");
return;
}
// Basic validation
if (isNaN(distance) || distance <= 0) {
alert("Please enter a valid distance greater than 0.");
return;
}
if (isNaN(passengers) || passengers 1) {
resultUnitElement.textContent = "per passenger";
} else {
resultUnitElement.textContent = "per trip";
}
}