How much CO2 does your flight produce?

Planes burn kerosene, and burning kerosene makes carbon dioxide. But turning that into a per-passenger number takes a methodology, and this page explains the one FlightBeat uses, so you know exactly where the climate estimate in our calculator comes from.

The method we use

We use the UK government's greenhouse gas conversion factors for company reporting, published by the Department for Energy Security and Net Zero and updated every June. It is the de facto standard for corporate travel reporting worldwide, and it publishes plain per-passenger-per-kilometer factors that a distance-based calculator can apply honestly.

The 2025 economy-class factors we apply:

• Short-haul international (under about 3,700 km): 0.12576 kg CO2e per passenger km.
• Long-haul international (over about 3,700 km): 0.11704 kg CO2e per passenger km.
• Short domestic hops (same country, under about 600 km): 0.22928 kg CO2e per passenger km. Short flights spend a bigger share of the trip climbing, which is why the per-km number is so much higher.

We multiply the factor by the great-circle distance between your two airports. The methodology already folds in an 8 percent uplift for indirect routing and delays, so no extra padding is needed.

What CO2e means, and why contrails count

The e in CO2e stands for equivalent. Flying warms the climate through more than carbon dioxide alone: contrails, nitrogen oxides, and water vapor at altitude add real warming of their own. The factors we use include an uplift for those non-CO2 effects, which roughly places total warming at 1.7 times the CO2 alone. Some calculators quote only the bare CO2 figure, which is why their numbers can look 40 percent smaller than ours.

Why it is an estimate

Your actual footprint depends on things no distance-based method can see: the exact aircraft and how new it is, how full the plane is, cabin class, winds, and routing that day. Business class takes roughly three times the economy footprint because a lie-flat seat takes three times the floor space. Treat our number as a fair planning estimate, not an invoice.

What this means for you: if you want to cut your flying footprint, the big levers are flying less often, flying economy, choosing nonstops (climbing once beats climbing twice), and favoring newer aircraft. Distance dominates everything, which you can see for yourself in the calculator.