Flight emissions calculator (UK government factors)
In short
A return economy flight from London Heathrow to New York (5,540 km each way) is 1.3 tonnes CO2e per passenger with the 2026 UK government factors, including the radiative forcing uplift, and 3.76 tonnes in business class. The calculator below works out any flight from the airports or the distance, the cabin and the number of travellers.
Updated by the Carbon Recycling team. Flight factors from the 2026 UK government conversion factors (DESNZ), the same ones our reporting software uses.
Pick two airports, or type a distance, choose the cabin and how many people flew, and see the emissions with and without the radiative forcing uplift.
Work out a flight's emissions
5,540 km each way · Long-haul from the UK · 11,080 passenger-km
1.69 t CO2ewith the radiative forcing uplift
1.00 t CO2e without it (0.1528 and 0.0904 kg CO2e per passenger-km)
2026 government flight factors (DESNZ), applied to the great-circle distance: they already include DESNZ's 8% uplift for indirect routes and delays. Radiative forcing counts the extra warming from emissions at altitude; the government recommends including it. Business travel is Scope 3, category 6.
Contains public sector information licensed under the Open Government Licence v3.0. Source: DESNZ, greenhouse gas reporting conversion factors.
Flight factors, 2026
Flight
Average
Economy
Premium economy
Business
First
Within the UK
0.2293
–
–
–
–
UK to Europe
0.1279
0.1258
–
0.1886
–
Long-haul from the UK
0.1528
0.1170
0.1873
0.3394
0.4681
Not touching the UK
0.1425
0.1092
0.1747
0.3166
0.4366
kg CO2e per passenger-km, including radiative forcing. A dash means DESNZ doesn't publish that cabin for that kind of flight; use the average.
Worked examples
London Heathrow to Edinburgh and back, two people: 534 km × 2 × 2 × 0.2293 = 0.49 t CO2e
London Heathrow to Madrid and back, economy: 1,243 km × 2 × 0.1258 = 0.31 t CO2e
London Heathrow to New York and back, business: 5,540 km × 2 × 0.3394 = 3.76 t CO2e
How Carbon Recycling helps
Add trips as they happen, upload a travel agent's report, or bring them in from your accounts, and Carbon Recycling works out each flight's distance and emissions with the right factor for the year. Business travel lands in Scope 3 category 6 of your Carbon Reduction Plan, with or without radiative forcing as you choose.
Data sources and licences
Contains public sector information licensed under the Open Government Licence v3.0. Source: DESNZ, greenhouse gas reporting conversion factors.
Airport positions are approximate, which is well within the precision the factors need. DESNZ does not endorse us.
Embed this tool on your website
Paste this code into your page and your readers can use the tool without leaving it. It's free. Please keep the credit link under the frame, so readers can see where the figures come from.
Distance × travellers × the government factor for the flight type and cabin. The distance is the great-circle distance between the airports; DESNZ's factors already add 8% for indirect routes and delays. Business and first class seats take more space, so they carry a bigger share of the plane's emissions.
›Should I include radiative forcing?
The UK government recommends it. Burning fuel at altitude warms the climate more than the CO2 alone, through contrails and nitrogen oxides, and the uplift accounts for that. Say in your report which you used; the calculator shows both.
›Which scope are business flights in?
Scope 3, category 6 (business travel). A Carbon Reduction Plan for public sector contracts must include it.
›What counts as short-haul and long-haul?
In the UK government factors, short-haul is a flight between the UK and an airport up to 3,700 km away, which covers most of Europe. Long-haul is anything further from the UK. Flights within the UK are domestic, and flights that don't touch the UK use the international factors.
›Why does a domestic flight have the highest factor per km?
Take-off and climbing burn the most fuel, and on a short flight they are a bigger share of the trip. Domestic flights are also flown by smaller planes that carry fewer people.
Get your figures and reports done in an afternoon
Add a year of bills and Carbon Recycling produces your footprint, PPN 006 Carbon Reduction Plan and SECR report, with every figure traced to its government factor. Prices are on the pricing page, from £59 a month + VAT.
They help us see how people use the site. Nothing optional runs unless you say yes.We'd like to use analytics and session recording to see how people use Carbon Recycling and make it better, and, if we advertise later, to see which adverts work. They only switch on if you say yes, and you can change your mind at any time with "Cookie settings" at the foot of each page.Cookie policy