Freight Carbon Calculator UK
This freight carbon calculator estimates UK road freight emissions for shippers, hauliers and procurement teams using official UK government 2025 conversion factors. See kg CO2e or tonnes, split between tank to wheel and well to tank.
- No sign-up needed
- Instant results in your browser
- Published UK data
How to use: set the distance and units, choose the vehicle and load type, enter the weight of goods carried, then read the emissions below. Add a pallet count for a per-pallet figure.
Your consignment
Methodology and data sources
Emissions are calculated on a weight-distance basis, the standard approach for freight reporting. The formula is emissions = distance in km × tonnes carried × emission factor, where the factor is expressed in kgCO2e per tonne-kilometre. Miles are converted to kilometres at 1 mile = 1.609344 km. The result is the CO2e of moving your goods over that distance, expressed in kilograms and tonnes.
The emission factors are the genuine published values from the UK Government Greenhouse Gas Conversion Factors 2026 (Department for Energy Security and Net Zero, with Defra), published June 2026. Two tables are used: the "Freighting goods" table provides the direct, tank-to-wheel (TTW) factors from burning the fuel, and the "WTT- delivery vehs & freight" table provides the well-to-tank (WTT) factors covering the upstream extraction, refining and distribution of the fuel. Adding TTW and WTT gives the full well-to-wheel figure most commonly required for Scope 3 category 4 (upstream transportation) reporting. The full dataset is on gov.uk: Greenhouse gas reporting conversion factors 2026.
The empty-running toggle switches which laden basis is used. Left ticked (the default and the recommended reporting basis) it uses the average laden factors, which reflect real-world operation where vehicles run part-full and often return empty. Unticked it uses the 100% laden factors, which assume the vehicle is full for the whole journey and therefore report a lower figure per tonne-km. Van factors are the diesel average for up to 3.5 tonnes and do not vary by laden basis in the DEFRA data, so the toggle has no effect on vans. These are 2026 factors intended for reporting on 2026 activity; assumptions current as of July 2026. Figures are estimates of typical fleet performance: for audited reporting, primary fuel data from your carrier (litres of diesel used) will always be more accurate than a distance-based estimate, and the GLEC Framework or ISO 14083 may apply for formal disclosures.
Frequently asked questions
How do I calculate CO2 emissions from road freight?
Multiply the distance travelled in kilometres by the weight of goods in tonnes, then by the DEFRA emission factor for that vehicle type in kgCO2e per tonne-km. This calculator embeds the DEFRA and DESNZ 2026 factors and does the conversion from miles automatically, giving you kgCO2e and tonnes CO2e.
What is the difference between tank-to-wheel and well-to-tank?
Tank-to-wheel (TTW) is the CO2e released when the fuel is burned in the engine. Well-to-tank (WTT) is the upstream CO2e of producing and delivering that fuel to the vehicle. Well-to-wheel is the two added together, and it is the figure usually needed for Scope 3 supply-chain reporting. This tool shows all three.
Which DEFRA factors does this use?
The 2026 UK Government Greenhouse Gas Conversion Factors (June 2026), specifically the "Freighting goods" table for direct emissions and the "WTT- delivery vehs and freight" table for upstream emissions, both on a per tonne-km basis. The exact values embedded are listed against each vehicle in the comparison and are drawn straight from the published dataset.
Should I use average laden or fully laden factors?
For most reporting, use average laden (the default). It reflects the reality that vehicles are rarely full every mile and frequently return empty, so it does not understate your footprint. Only use the 100% laden basis if you genuinely have dedicated, always-full trunking and can evidence it.
Why is a van's CO2 per tonne so much higher than an artic's?
Because a van carries very little weight relative to the fuel it burns, so each tonne of goods absorbs a large share of the emissions. A 44 tonne artic spreads its fuel burn across a much heavier payload, giving a far lower kgCO2e per tonne-km. Consolidating freight onto larger vehicles is one of the most effective ways to cut transport emissions.
Is this accurate enough for our ESG report?
It uses the official DEFRA and DESNZ factors correctly, so it is suitable for indicative and management reporting. For assured or regulated disclosure, use primary data (actual fuel burned) where you can obtain it from your carrier, and apply the relevant framework such as GLEC or ISO 14083. Always cite the factor year you used.
Cut the emissions, not just the report
Lower-carbon transport usually comes from better consolidation, higher load fill and the right vehicle for the lane, which is exactly what a well-matched operator delivers. Brief CTS on what you move and we place it before vetted UK providers who can improve both cost and carbon. Free, no obligation. See contract logistics and transport and warehousing.
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