Flight Carbon Footprint Calculator
Calculate the CO₂ emissions from your flight in kg and tonnes.
Compare economy vs. business class and see real-world equivalents for your carbon footprint.
How It Works
Aviation accounts for roughly 2–3% of global CO₂ emissions. Once high-altitude warming effects are counted, its total climate impact is estimated at 2 to 4 times that figure. This calculator uses emission factors of the kind published by the UK government’s Department for Energy Security and Net Zero (DESNZ) and equivalent bodies.
Emissions per kilometer are not constant, and short flights are the worst. Takeoff and the climb to cruise burn a disproportionate share of a flight’s fuel. On a 500 km hop that phase is most of the trip; on a 10,000 km haul it is a rounding error spread over ten times the distance. So the same aircraft emits far more per passenger-kilometer on a short flight than on a long one, and a calculator using one flat number gets short flights badly wrong.
The bands below are economy class, per passenger per kilometer, excluding radiative forcing:
| Flight length | Factor (kg CO₂e per passenger-km) |
|---|---|
| Under 1,000 km (domestic / regional) | 0.246 |
| 1,000–3,700 km (short-haul) | 0.151 |
| Over 3,700 km (long-haul) | 0.148 |
Read that table twice. A 900 km flight emits more per kilometer than a 9,000 km flight, by about two thirds. It is the single most counterintuitive fact about aviation emissions, and it is the reason a train usually beats a plane on a short route by a much wider margin than people expect.
What is Radiative Forcing (RF)? Aircraft emit more than CO₂: water vapor, nitrogen oxides, soot, and the condensation that forms contrails. At cruising altitude (30,000–40,000 feet) these non-CO₂ effects cause additional warming estimated at roughly 1.9× the CO₂ alone. Including RF gives a fuller picture of the climate impact. Many calculators leave it out, so this one offers both and tells you which you are looking at.
Cabin class multipliers: Business and first class passengers occupy more space per person, meaning fewer seats per aircraft and higher emissions per passenger.
| Class | Multiplier | Reason |
|---|---|---|
| Economy | ×1.0 | Baseline |
| Premium Economy | ×1.6 | More space, fewer seats |
| Business | ×2.9 | Flat beds, much larger footprint |
| First Class | ×4.0 | Private suites, extreme space use |
Unit conversion: 1 mile = 1.60934 km.
Everyday equivalents (approximate):
- Driving a typical petrol/gasoline car emits ~0.21 kg CO₂ per km
- One week of average home electricity use ≈ 50 kg CO₂
- One tree absorbs approximately 20–25 kg CO₂ per year
Comparing transport modes (per passenger per km, CO₂ only):
| Mode | CO₂ per km |
|---|---|
| Domestic / regional flight | ~0.25 kg |
| Short-haul flight | ~0.15 kg |
| Long-haul flight, economy | ~0.15 kg |
| Long-haul flight, business | ~0.43 kg |
| Car (petrol, driver only) | ~0.17–0.21 kg |
| Car (petrol, 4 people) | ~0.04–0.05 kg per person |
| Coach / Bus | ~0.03–0.07 kg |
| Train (electric) | ~0.03–0.06 kg |
A full car of four beats every flight on this list, which is worth knowing before anyone feels virtuous about driving alone.
Carbon offset programs: Airlines and third parties sell offsets covering tree planting, renewable energy funding, and methane capture. Effectiveness varies enormously, and several large forestry schemes have been found to over-credit what they actually store. Independent offsetting through a verified registry (Gold Standard, Verra VCS) is generally treated as more reliable than the checkbox at the end of an airline booking, though the honest summary is that not taking the flight is the only method nobody disputes.
How we build and check this calculator
This calculator runs entirely in your browser, so the numbers you enter stay on your device. The math behind it is written by hand and tested against worked examples and standard references before the page goes live.
SuperGlobalCalculator is independently built and maintained. See how we build and verify our calculators.