Free Eco Home Calculators

Carbon Footprint Calculator

1 min read Last updated 20 May 2026
Quick answer A typical UK home emits about 2.7 tonnes of CO2e per year — roughly 2.2 tonnes from gas heating and 0.7 tonnes from electricity (offset by 0.2 tonnes of grid decarbonisation since 2020). Switching to a heat pump cuts the gas emissions by around 70%.

The Carbon Footprint Calculator estimates your home's annual CO2e emissions from gas, electricity and oil, applies a solar offset if you have panels, compares the result against the UK average, and suggests reduction actions ranked by impact. Emission factors are sourced from BEIS / DESNZ official conversion factors.

Carbon Footprint Calculator

Estimate your home's annual carbon emissions and potential reductions.

Check your annual gas statement. UK average is ~12,000 kWh.
UK average is ~3,100 kWh.

See 20 real-world examples

Each link below runs this calculator with real UK city and property inputs and publishes the exact computed savings, payback time, install cost and CO2 figures.

Browse all calculator examples →

How this calculator works

Emission factors are the official UK Government Greenhouse Gas Reporting figures: gas 0.183 kg CO2e/kWh, grid electricity 0.233 kg CO2e/kWh (2024 grid average), heating oil 2.54 kg CO2e/litre. Solar offset assumes generation displaces grid imports at the same emission factor. The "trees needed" figure converts at 22 kg CO2 sequestered per mature broadleaf tree per year (Forestry Commission guidance).

Sources & references

Frequently asked questions

Why does switching to a heat pump cut emissions?

A gas boiler emits 0.183 kg CO2 per kWh of useful heat. A heat pump uses 1 kWh of electricity to produce 3 kWh of heat (COP 3), so it emits 0.233 ÷ 3 = 0.078 kg CO2 per kWh of heat — about 57% lower today, dropping further as the grid decarbonises.

Should I include flights and food?

This calculator covers home energy only. UK average per-person emissions including transport, food, and consumption are around 8-10 tonnes per year. WWF Footprint Calculator covers the full picture.

Where do the emission factors come from?

They're the UK Government Greenhouse Gas Conversion Factors published annually by DESNZ (Department for Energy Security and Net Zero). The grid electricity figure updates yearly as the generation mix changes.

How accurate is "trees needed"?

It's a rough indicator. A mature UK broadleaf tree absorbs about 22 kg CO2 a year. Saplings absorb much less; very mature woodland more. The figure helps make abstract tonnes tangible — it's not a substitute for genuine carbon offsetting.

Is solar self-consumption double-counted?

No. We offset the total solar generation against grid emissions. In reality, only the self-consumed portion directly avoids grid imports — exported electricity displaces grid generation elsewhere, which is also a real emission saving.

Tool: Carbon Footprint Calculator. Last reviewed: . Figures based on Ofgem price cap, gov.uk grant guidance, and Energy Saving Trust advice. Verify scheme eligibility with your installer before commissioning work.