Air freight (long-haul): carbon footprint per tonne-km (with RF)
Live factor value
0.89939 kgCO2e per tonne-km (with RF)
Source: UK DESNZ greenhouse-gas conversion factors, 2026 (revision 2). Factor set desnz-2026-r2.
Air freight is in a different universe from every other mode: the official DESNZ 2026 long-haul factor, live below with radiative forcing, is roughly thirty-five times rail freight and over fifty times container shipping per tonne-kilometre. Keeping a tonne of anything airborne simply takes enormous energy.
The business consequence: a product's whole footprint can hinge on one routing decision. Flying a tonne of goods from East Asia instead of shipping it adds several tonnes of CO2e — more than the manufacturing footprint of many products being carried. Air freight earns its place only where days genuinely matter; 'sea-air' hybrids and better forecasting are how shippers cut it.
Worked example
One tonne flown Hong Kong–London (~9,500 tonne-km): 9,500 × 0.89939 = 8,544 kgCO2e.
Measure your own with the free freight calculator.
Frequently asked questions
- How much worse is air freight than sea freight?
- Around fifty times per tonne-km on the official 2026 figures (long-haul, with radiative forcing, versus the average container ship). Even against road haulage the multiple is roughly eightfold.