Carbon · Energy and travel

Household Carbon Footprint Calculator

Estimate your household's CO₂e from home electricity, heating fuel, car and flights. Each line is activity × emission factor. Default factors come from the UK Government 2025 conversion factors; replace any of them with factors for your country and year.

Included

Home electricity
Heating fuel (gas, oil, LPG)
Car fuel or EV charging
Flights

Not included

Food and drink
Purchased goods and services
Public transport (rail, bus, coach)
Upstream fuel supply, grid losses and vehicle manufacture

The result is a partial footprint for the categories above, not a complete total.

Home electricity

Electricity used per year (kWh)

From your bills. Include heat-pump or electric heating here if it is on the same meter.

Emission factor source

Factor

Unit (CO₂e)

Location-based, Scope 2 electricity generated (UK grid average). Excludes transmission and distribution losses, which the same set reports separately (0.01853 kg CO₂e/kWh).

Heating fuel

Fuel burned at home

Fuel used (kWh)

Unit

Factor (kg CO₂e per kWh)

Fuel burned, not heat delivered. kWh on a gross calorific value basis, as on most UK bills. Gas in m³? Use the gas to kWh converter.

Car

Car type

Distance per year

Unit

Fuel consumption

Unit

Factor (kg CO₂e per litre)

Fuel used: 840 L. Default: Petrol (UK average biofuel blend).

Flights

Total km flown per year in each band, counting every leg — a return trip of 1,000 km each way is 2,000 km.

Domestic, to/from UK (km)

Short-haul, to/from UK (km)

Long-haul, to/from UK (km)

International, to/from non-UK (km)

Include radiative forcing (non-CO₂ effects at altitude). The UK factors are published with and without this uplift.

Estimated household footprint from the categories entered

4.81 t CO₂e

= 4,809 kg CO₂e per year. Direct emissions only. Excludes food, goods and services, and public transport.

Line	kg CO₂e	Share
Home electricity	620	13%
Heating fuel	2,196	46%
Car fuel	1,738	36%
Flights	256	5%

What drives the result

One input changed at a time. These show sensitivity, not a target.

Scenario	Total t CO₂e	Change, kg
Your inputs	4.81	—
Electricity factor 50% lower	4.5	−310
Electricity factor 50% higher	5.12	+310
Drive 25% fewer km	4.37	−435
Half the flight km	4.68	−128
No flights	4.55	−256

Factors used

Every factor field above is editable.

Line	Factor & unit	Source	Year	Geography
Electricity	0.177 kg/kWh CO₂e	UK Government GHG Conversion Factors for Company Reporting 2025 (DESNZ), "UK electricity" factor	2025 factor set	United Kingdom
Heating — Natural gas	0.18296 kg CO₂e/kWh	UK Government (DESNZ), Scope 1 fuels	2025 factor set	United Kingdom
Car — petrol	2.06916 kg CO₂e/L	UK Government (DESNZ), Scope 1 fuels	2025 factor set	United Kingdom
Flights (with RF)	0.12786–0.22928 kg CO₂e/passenger-km	UK Government (DESNZ), business travel – air	2025 factor set	Flights to/from the UK (international band: non-UK)

How each factor and boundary was chosen is on the methodology page.

How the calculation works

Electricity = kWh × grid factor

Heating = fuel kWh or litres × fuel factor

Car = (distance ÷ 100 × L/100 km) × kg CO₂e/L

EV = distance ÷ 100 × kWh/100 × grid factor

Flights = passenger-km × flight factor

Total (t) = sum of lines (kg) ÷ 1,000

mpg is converted to litres with 1 mile = 1.609344 km, 1 UK gallon = 4.54609 L and 1 US gallon = 3.785411784 L.

Sources. Heating, car-fuel and flight defaults: UK Government GHG Conversion Factors for Company Reporting 2025 (DESNZ), flat-format file — Scope 1 fuel combustion factors (kg CO₂e; kWh on gross calorific value; petrol and diesel are UK average biofuel blends) and business-travel air factors for an average passenger, excluding well-to-tank. Electricity presets are the same verified factors used by the Electricity CO₂ Calculator. Upstream fuel supply, grid losses and vehicle manufacturing are outside this boundary. UK factors describe UK fuels and flights; elsewhere, use local factors where you have them.

The guide to calculating a footprint from energy and travel explains the boundary and the choice of factors. For electricity on its own, see how to calculate electricity CO₂; to compare car, rail, coach and air per trip, see the transport carbon comparison. Constants and boundaries are documented on the methodology page, and more carbon tools are in the Carbon Footprint hub.

Frequently asked questions

What does this calculator include?

Home electricity, heating fuel (natural gas, heating oil or LPG), car fuel or electric-car charging, and flights. Food, purchased goods and services, and public transport are outside this boundary, so the result is not a complete carbon footprint. It is the sum of the lines you enter, for the period your inputs cover.

Is this a personal or a household footprint?

Household. Electricity and heating bills, the car and the flights you enter usually describe everyone at the address. To get a rough per-person figure, divide by the number of people only if they all share those bills, car and flights.

Is the result CO₂ or CO₂e?

The default factors are all CO₂e (carbon dioxide equivalent) from the UK Government 2025 conversion factors, and both electricity presets are CO₂e. If you enter your own factor, use a CO₂e factor so the total stays on one basis.

Are these direct or lifecycle emissions?

Direct. Fuel factors are combustion (Scope 1) factors, the UK electricity factor covers generation only, and flight factors exclude the separate well-to-tank (fuel supply) factors. Upstream fuel supply, grid losses and vehicle manufacturing are not included.

How should I enter flights?

Enter the total passenger-km flown in each distance band, counting every leg. A return trip of 1,000 km each way is 2,000 km. You can choose whether flight factors include the radiative-forcing uplift for non-CO₂ effects at altitude; the UK factors are published both ways.

Should I use my own emission factors?

Yes, if you have factors for your country and year. Every factor field is editable. Your source then determines what the result covers, so keep its gas basis (CO₂e) and boundary consistent across lines.