Enter your departure city, destination, cabin class, and number of passengers to calculate your flight's CO₂ emissions. The Flight Carbon Footprint Calculator breaks down your total carbon output per passenger and for the whole group, with a visual split of base emissions versus cabin-class multiplier impact.
Total CO₂ Emissions
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CO₂ per Passenger
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Total in Metric Tonnes
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Trees Needed to Offset (1 year)
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Total Distance Flown
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The calculator uses the flight distance, a base CO₂ emission factor (approximately 0.115 kg CO₂ per passenger-km), a cabin-class multiplier to reflect seat size and weight allocation, and an optional Radiative Forcing Index (RFI) of 1.9 to account for high-altitude warming effects beyond CO₂ alone. The result is multiplied by the number of passengers and trip legs.
RFI captures the additional climate warming caused by aircraft flying at high altitudes — including contrail formation, ozone effects, and water vapour. Aviation's total climate impact is roughly 1.9× greater than the CO₂ emissions alone, which is why many organisations like ICAO recommend including RFI in flight footprint estimates.
Different cabin classes occupy different amounts of space and weight on the aircraft. Business and first-class seats are larger and heavier, meaning each passenger in those classes is allocated a greater share of the flight's total fuel burn. Economy passengers share a much smaller footprint per person because more people fit in the same space.
Carbon offsets are verified credits representing one tonne of CO₂ removed from or prevented from entering the atmosphere — for example, by protecting forests, funding renewable energy, or capturing methane. Purchasing offsets equivalent to your flight emissions allows you to counterbalance your carbon footprint and support climate projects worldwide.
The great-circle (straight-line) distance between airports is the standard used for flight emissions calculations. You can find airport-to-airport distances from resources like the ICAO route database, Google Flights, or dedicated flight distance tools. Enter the one-way distance; the calculator will double it automatically for round trips.
A single mature tree absorbs roughly 21 kg of CO₂ per year on average. The calculator divides your total CO₂ emissions by this figure to estimate how many trees would need to grow for a full year to absorb an equivalent amount — giving you a tangible sense of your flight's environmental cost.
Short-haul flights are generally worse per kilometre of distance because take-off and landing — the most fuel-intensive phases — make up a much larger proportion of the total trip. Long-haul flights burn more total fuel but spread the per-km footprint across more distance, making them slightly more efficient on a per-km basis.
Flying economy class on a direct route, on a newer and larger aircraft, produces the lowest per-passenger carbon footprint. Avoiding stopovers reduces unnecessary take-offs and landings, and economy class shares the aircraft's weight impact among the most passengers possible.