Flight carbon footprint calculator
Pick a route and a cabin to see the CO₂ emissions of the flight, per passenger. Cabin matters more than most calculators admit — on a long-haul flight a business seat carries about 2.9× the footprint of an economy one on the same aircraft (1.5× on a short hop). Free, and no sign-up needed.
Popular routes, economy vs business
One way, per passenger.
| Route | Economy | Business |
|---|---|---|
| LHR → JFKLondon to New York | 648 kg CO₂ | 1.9 t CO₂ |
| LAX → NRTLos Angeles to Tokyo | 1.0 t CO₂ | 3.0 t CO₂ |
| CDG → DXBParis to Dubai | 613 kg CO₂ | 1.8 t CO₂ |
| SIN → SYDSingapore to Sydney | 737 kg CO₂ | 2.1 t CO₂ |
| FRA → GRUFrankfurt to Sao Paulo | 1.1 t CO₂ | 3.3 t CO₂ |
| ZRH → LHRZurich to London | 114 kg CO₂ | 154 kg CO₂ |
| JFK → LAXNew York to Los Angeles | 471 kg CO₂ | 1.2 t CO₂ |
| DXB → SINDubai to Singapore | 684 kg CO₂ | 2.0 t CO₂ |
Common questions
How is a flight's carbon footprint calculated?
Great-circle distance between the two airports, multiplied by an emissions factor per passenger-kilometre for the cabin you fly. The factors are the UK government's 2026 conversion factors (DESNZ/DEFRA), which already include an 8% allowance for indirect routing and holding. Short flights use a higher rate per kilometre than long ones, because take-off and climb burn a fixed chunk of fuel whatever the distance: about 0.23 kg per kilometre on a short domestic hop, 0.13 kg on short-haul economy and 0.12 kg on long-haul economy.
Why does business class emit more than economy?
Because the aircraft's emissions are shared out by the space each passenger takes. On a long-haul flight a lie-flat business seat occupies roughly three times the floor of an economy seat, so it carries roughly three times the share, and first class about four times. On a short-haul flight business is usually an economy seat with the middle one left empty, so it counts about 1.5 times.
Is a direct flight better than connecting?
Usually, yes. Take-off and climb burn far more fuel per kilometre than cruise, so two short legs emit more than one long one covering the same ground — on top of the extra distance a connection normally adds.
Does this include radiative forcing?
Yes. Contrails and nitrogen oxides released at altitude warm the climate on top of the CO₂ itself, and the government factors used here include that effect, which adds roughly 70% to the CO₂ alone. The result is the flight's full climate impact in CO₂-equivalent. Calculators that report CO₂ only, such as ICAO's, show lower figures for the same flight.
How accurate is it?
It is an estimate, and the honest error bars are wide. Real emissions depend on the aircraft type, its age, how full it is, the freight in the hold, and the winds on the day. Treat the number as the right order of magnitude for comparing routes and cabins, not as a measurement of your specific flight.
See it for every flight you take
routebook keeps a running total across your whole flight history — by year, by airline, by cabin — next to your map, your stats and your badges. Logging is free, forever.
Start your flight log — freeMore tools: the distance calculator and the compensation checker.