Understand your journey
Travel emissions calculator
Estimate the emissions from a rail journey, car trip or flight. See what contributes to your result, then explore carbon credit options with our team.
How are you travelling?
About your estimate
Clear assumptions.
Useful next steps.
For worked examples, read how to calculate travel carbon emissions. For cabin class and additional warming, see how flight emissions are calculated.
What is included?
We multiply distance by the relevant 2026 UK Government conversion factor. Rail and flight factors are per passenger. Car factors are per vehicle, with the total divided by the number of occupants to show each person’s share. A return journey doubles the one-way distance.
Results include travel operations and fuel or energy supply (well-to-tank), plus electricity transmission and distribution for electric and plug-in hybrid cars. Vehicle manufacture, infrastructure, accommodation and other activities are excluded. This is a journey estimate, not a full life-cycle assessment.
How are flights treated?
Enter the direct airport-to-airport distance. The published flight factors already include an 8% distance allowance, so we do not add it again. The optional additional warming effect uses the difference between government factors with and without radiative forcing. It is shown separately because these effects are uncertain and are not part of a standard greenhouse gas inventory total.
For connecting flights or mixed cabin classes, calculate each leg separately. The government’s full factor workbook includes the destination-based haul definitions.
Where do the factors apply?
Car and domestic rail estimates use UK averages. Electric car estimates use the UK electricity mix. The international rail factor is based on Eurostar and is not representative of every overseas rail network. Flight factors distinguish UK domestic, UK short haul, UK long haul and international flights between non-UK countries.
Source: Department for Energy Security and Net Zero, 2026 conversion factors, July revised flat file, version 1.2. Contains public sector information licensed under the Open Government Licence v3.0.
How does this relate to carbon credits?
One carbon credit represents one tonne of CO₂ equivalent reduced or removed by a qualifying project. Your result is an estimate of travel emissions, not an automatic purchase quantity or a claim that a journey is carbon neutral. Our team can help you review the basis, available projects, quantities and retirement records before you decide to purchase.