Welcome to the web's leading carbon footprint calculator

Sustrax Vita follows the methodology outlined by the UK Government, using the "Greenhouse gas reporting: conversion factors" published annually by Defra. The system is current using the 2025 emissions factors. The main exception to this is the country specific electricity factors used for location-based calculations. A full list of these, along with the methodology is provided by Carbon Footprint Ltd, on the CaDI (Carbon Database Imitative) these can be found here: https://www.carbondi.com/#electricity-factors/emissions-factor-details/. Where available, the emissions factors provided cover emissions from generation of the electricity, transmission & distribution (T&D) losses, and well-to-tank (WTT) emissions. Sustrax Vita uses emissions factors which take account of all greenhouse gases (i.e. CO2, N2O, methane etc.) released by the activities, with the results presented in units of metric tonnes of CO2 equivalent (CO2e). In most cases that means the results will be slightly higher than if calculating CO2 only. The calculations of emissions from fuels are Scope 1, meaning the direct GHG emissions from the combustion of the fuels. The calculations also include the well-to-tank (WTT) Scope 3 emissions associated with extraction, refining, distribution, storage and retail of the fuels.

Sustrax Lite follows the methodology outlined by the UK Government, using the "Greenhouse gas reporting: conversion factors" published annually by Defra. The system is current using the 2025 emissions factors. The main exception to this is the country specific electricity factors used for location-based calculations. A full list of these, along with the methodology is provided by Carbon Footprint Ltd, on the CaDI (Carbon Database Imitative) these can be found here: https://www.carbondi.com/#electricity-factors/emissions-factor-details/. Where available, the emissions factors provided cover emissions from generation of the electricity, transmission & distribution (T&D) losses, and well-to-tank (WTT) emissions. Sustrax Lite uses emissions factors which take account of all greenhouse gases (i.e. CO2, N2O, methane etc.) released by the activities, with the results presented in units of metric tonnes of CO2 equivalent (CO2e). In most cases that means the results will be slightly higher than if calculating CO2 only. The calculations of emissions from fuels are Scope 1, meaning the direct GHG emissions from the combustion of the fuels. The calculations also include the well-to-tank (WTT) Scope 3 emissions associated with extraction, refining, distribution, storage and retail of the fuels. Sustrax Lite and Sustrax Lite X do not include all Scope 3 emissions, such as waste, water, commuting, and freighting. If you need to include these elements, you can upgrade to Sustrax Lite XL on the 'upgrade' page. If you are requiring additional scope 3 categories (such as purchased goods & services), please contact us at info@carbonfootprint.com to hear more about more services we can provide for your business.

Sustrax Vita is designed to calculate your annual carbon footprint. To get the most accurate results, please think about your activities and energy usage over the past 12 months. This will give you a comprehensive picture of your yearly emissions.

A carbon footprint is a measure of the impact our activities have on the environment in terms of the amount of greenhouse gases produced, measured in units of carbon dioxide equivalents (CO2e). A carbon footprint comprises three parts, Scope 1 (direct), Scope 2 and Scope 3 (indirect) emissions.

Direct emissions are produced by sources which are owned or controlled by the reporting organisation and include electricity use, burning oil or gas for heating, and fuel consumption as a result of business travel or distribution. Direct emissions correspond to elements within scope 1 of the GHG Protocol.

Indirect emissions result from a company’s upstream and downstream activities. These are typically from outsourced/contract manufacturing, and products and the services offered by the organisation. Indirect emissions correspond to scopes 2 and 3 of the GHG Protocol.

Climate change is a global threat which will impact the lives of everyone on the planet. Over the past two decades the effects of climate change have accelerated. Considerable evidence exists proving climate change has been exacerbated by human activity. Changes in our post-industrial lifestyles have altered the chemical composition of the atmosphere, generating a build-up of greenhouse gases – primarily carbon dioxide, methane, and nitrous oxide levels – raising the average global temperature. The consequences are already evident and will continue to worsen unless significant action is taken and quickly. Sea level will continue to rise and local climate conditions to be altered, causing an increase in extreme weather events, affecting forests, crop yields, and water supplies. This can lead to homelessness, famine and conflict as resources become scarcer. Environmental pollution and climate change affect human health, accelerate species extinction, and disrupt vital ecosystems. Ambient (outdoor) air pollution is responsible for at least 4.2 million human deaths each year (WHO 2022). In addition to this, poor air quality and issues of clean water availability leave us more susceptible to diseases such as COVID-19. Combined with rises in temperature and deforestation (from direct human action and climate change related events), resulting in the displacement of animals from their native habitats, the frequency of disease occurrence will increase, as disease will transfer from animals to other geographical areas and larger human populations. It is vital that all individuals, businesses, organisations and governments work towards the common goal of reducing greenhouse gas emissions. This carbon footprint assessment will enable your organisation to do its bit by monitoring, reducing and potentially offsetting its emissions.

Carbon footprint calculations are typically based on emissions from a 12-month period, which is what we recommend.

The new Sustrax Vita calculator includes “Well-to-Tank” (WTT) emissions in its calculations, which the classic calculator did not. This means it accounts for the greenhouse gases released during the production and transportation of fuel before it reaches your vehicle/home, giving a more complete picture of your total emissions.

Our electricity reporting for green tariffs shows zero supplier emissions, reflecting the procurement of renewable energy. It is worth noting that accounting for Transmission & Distribution (T&D) losses and Well-to-Tank (WTT) emissions is complex. For market-based reporting, while Renewable Energy Guarantees of Origin (REGOs) or equivalent certificates cover generation, it is often not explicitly clear if they also cover T&D losses. Therefore, T&D emissions may not be zero and typically align with location-based factors. For WTT emissions, representing upstream activities, there are currently a lack of specific renewable energy factors so zero has been assumed for 100% green tariffs. We simplify reporting for user clarity but acknowledge these nuances and are exploring more detailed implementation for the future.

If you have taken multiple journeys in the same vehicle, or same type of transport (e.g. national rail), you can combine the mileage into one record if you wish - the total emissions will be the same in both cases.

This enables a more accurate calculation of your location-based emissions from electricity usage, as the location-based factor depends on how the electricity is generated in the region (e.g. from coal, gas, nuclear, renewables etc.).

There are two ways car and motorbike emissions can be recorded in Sustrax. These are listed below in order of accuracy: 1) Type of fuel, and the amount of fuel used 2) Size of vehicle, type of fuel used, and distance travelled

Petrol/LPG/CNG - up to a 1.4-litre engine Diesel - up to a 1.7-litre engine Others - vehicle models of a similar size Mopeds/scooters - up to 125cc.

Petrol/LPG/CNG - from 1.4-litre to 2.0-litre engine Diesel - from 1.7-litre to 2.0-litre engine Others - vehicle models of a similar size Motorbike - 125cc to 500cc

Petrol/LPG/CNG - 2.0-litre engine + Diesel - 2.0-litre engine + Others - vehicle models of a similar size Motorbike - 500cc +

For any car/motorbike where you do not know the engine size, choose the average.

It is recommended to add a separate or combined record for the kWh of car charging within the Electricity tab as the Cars tab only covers fuel and scope 3 related emissions.

Firstly the distances are calculated between the airports selected, using the great-circle method. This is then multiplied by the appropriate emissions factor specific to the type of flight (UK domestic, short haul, long haul, or international) and the class of seat taken (economy class, business class, etc.). The emissions factors include the distance uplift to compensate for planes not flying using the most direct route i.e. flying around international airspace, stacking, etc.

• Domestic flights occur between UK airports only. • Short-haul are flights to/from the UK up to 3,700 km, which typically include Europe. • Long-haul flights are flights to/from the UK over 3,700 km, which are typically non-European destinations. • International flights are any flights where both the departure and destination are non-UK countries. (note: if the calculation method is Select Airports, this category is selected automatically)

Different emission factors are calculated according to the relative area of the plane occupied by different seating classes. For example, a passenger in a first class seat would occupy a larger area compared to an economy class passenger, therefore they are attributed a larger percentage of the overall plane emissions.

The emission factors assume an average occupancy of the plane.

Emissions from planes at high altitudes impact climate change more than if the emissions were released at ground level. To take account of this, the emissions from planes are factored up by a radiative forcing factor. Radiative forcing is included in our calculations by default.

The factors are calculated based on publicly available UK data from major service operators, national statistics, and the department for transport.

Don't worry! You can estimate the distance between two stations - we recommend using a website such as Google Maps to find the road distance. Road distances are usually a good approximation to rail distances.

This is a measure of the emissions caused through the manufacture, delivery and disposal of products and services we buy. Most carbon footprint calculators ignore this part of your footprint, but without it you may risk under estimating your total footprint quite considerably.

Spend factors are released by the UK government, in their Annual greenhouse gas and carbon dioxide emissions relating to UK and England consumption. https://www.gov.uk/government/statistics/uks-carbon-footprint

Country averages are consumption-based footprints per person per year. United Kingdom: Defra (2023), Carbon footprint for the UK and England to 2023 (Open Government Licence v3.0). Other countries: OECD (2022), Greenhouse gas footprint indicators, final-demand greenhouse gas per capita (CC BY 4.0), accessed September 2026. These figures include public services and infrastructure, so their coverage is broader than your personal entries. The European Union average (5.66 metric tons), the worldwide average (4.86 metric tons) and the worldwide target (2 metric tons) are the reference figures carried over from the original calculator. They use different years and methods from the country averages, so the lines are a guide rather than a like-for-like comparison. Where a country has no published average, no figure is shown.

Use kWh from a bill, fuel quantities or journey details when you have them. Estimates help when you only know your spending or home size. They use averages and cannot capture every household, tariff, vehicle or journey. There is no measured accuracy range for these estimates.

Electricity and gas estimates turn your spending or home size into annual kWh, then use the normal energy emissions factors and your electricity tariff/supplier settings. Fuel and Cars divide spend by a reference price or your own price per litre or kg, then use fuel-quantity factors for combustion and upstream emissions. Flights, Public Transport and Spend use industry-average emissions factors per pound. These methods can give different results.

No. Fuel and Cars start with an editable Reference price. Petrol and diesel have UK and EU country references. Heating oil uses a UK reference; bottled gas, coal, wood logs and pellets use clearly labelled UK supplier examples. Where a local price is unavailable, the form explicitly identifies the UK fallback. These are dated estimates, not live quotes or local averages for every country. The source and date are shown beside the price. Choose My price or edit the number if you know what you paid. Local prices, bottle sizes, bulk purchases and wood moisture can make a substantial difference. Changing country or fuel restores its reference price. Natural gas is estimated in its own tab; specialist fuels and blends remain in Fuel used.

For purchases and travel, Total spend counts the amount once: use it for one flight booking, one purchase or your combined total for the year. Weekly multiplies by 52 and Monthly by 12, assuming that spending continues throughout the year. For occasional or seasonal spending, enter the combined total instead. Electricity and gas always estimate annual consumption: their Total spend option needs your combined energy spend for the whole year, because a full year's standing charges are deducted. Enter electricity and gas costs separately if you have a combined bill.

Results show your spending in the currency you selected. Total spend is shown once; weekly and monthly spending is shown as an annual total in that same currency. Where conversion is needed to calculate emissions, the calculator uses the latest available IMF exchange-rate data bundled with it. These are reference rates, not live or bank transaction rates. For Fuel and Cars, spend and the price per litre or kg must use the same selected currency. Changing currency updates reference fuel prices; custom prices are cleared so you can enter the price in the new currency. Energy bills, prices per kWh and standing charges must also use the same selected currency; changing currency does not convert a tariff.

The energy estimator subtracts 365 daily standing charges from annual spending, then divides the remaining amount by the price per kWh. A standing charge buys no energy. Use your own prices if you know your tariff, and set the standing charge to 0 if your spending already excludes it or your tariff has none. Enter prices in the selected currency's main unit: for example, GBP 0.26 for 26 pence per kWh. If spending does not cover the standing charge, there is no positive consumption estimate to use.

No. They are reference prices from the data supplied with the calculator and may cover different periods across countries. They do not update live. The UK reference is an Ofgem Great Britain Direct Debit average for a stated cap period, not a quote for every supplier, payment method or Northern Ireland. Your own bill's prices are preferable, especially when tariffs have changed during the year.

The starting bands come from Ofgem's July 2026 Typical Domestic Consumption Values. Mapping them to home sizes, interpolating the small-house value and adjusting for occupants are our modelling assumptions, not published Ofgem coefficients. Home estimates are limited to the UK and supported Eurostat countries: electricity uses household consumption ratios, and European gas uses heating degree days, a measure of how cold it is and for how long. US bill prices remain available, but US home baselines and ten other countries' unsupported reference constants are withheld. Insulation, heating habits, heat pumps, solar panels and electric vehicles are not individually modelled. Only add gas for a home that uses it. Use measured consumption or your own bill and tariff when no supported home estimate is available.

Bus and taxi share a land-transport industry factor, so the same spend produces the same estimate. Fuel/Cars now use fuel-quantity factors: petrol and diesel have their own factors. Heating oil and paraffin both mean kerosene in this estimator and use the Burning oil factor. The reference or custom price per unit also affects the estimated quantity. Use the detailed form if your fuel is a different product or blend.

Fuel/Cars provide a reference price automatically. Your actual price per litre or kg is preferable when known; enter it in the same currency as the spend. For a bag or bottle, divide the fuel-only cost by its fuel weight. Exclude separately charged delivery fees and bottle deposits; use a representative average price for recurring spend. Estimates assume the purchased fuel is used during the period. Household coal means domestic coal, not an unspecified smokeless blend. Wood logs and pellets keep their biomass factors and separately reported biogenic CO2; they are not zero-carbon. Old fuel/car spend entries need explicit recalculation with a reference/custom price or measured usage. A current reference does not reconstruct an old purchase price. Flight spend uses a broad UK industry factor, including for foreign-currency tickets. A more expensive ticket can produce a higher estimate for the same flight. It does not separately model route, cabin or distance, and the exact treatment of additional aviation non-CO2 effects remains unverified. Prefer journey details when available.

Choose one method for each activity. Do not add the same electricity bill as both an energy estimate and general Spend, or the same journey as both a spend estimate and a detailed journey. Exclude costs already entered elsewhere from any combined spending total. You can mix methods for different activities as long as they do not overlap.

The fuel kWh option uses Gross Calorific Value (Gross CV), consistent with the gas estimator. Check that a supplied energy quantity uses that basis. Petrol and Diesel are shorter input labels for the average biofuel-blend options; saved records can show the full factor names.

Energy entries retain calculated kWh but not the original bill, tariff, home size or occupancy inputs; keep those details separately. New fuel/car spend entries retain the unit price, country, estimated quantity and, for references, the source date and conversion details. These price snapshots are preserved when reopening an unchanged record. Spend entries retain their original spend, period and currency information, but do not archive the exact emissions-factor release. Recalculation may differ after reference data changes. Older fuel/car spend records without a unit price are not automatically corrected: reopen them and recalculate using a reference or your own price, or replace them with actual fuel usage.