Free carbon & energy calculators
Turn everyday numbers — electricity, fuel, flights — into estimated CO₂ emissions. Each tool explains the data and assumptions behind its result.
CO₂ calculators
Each tool targets one question and explains the method behind its result.
kWh to CO₂
Convert electricity use in kilowatt-hours to carbon emissions.
Miles driven to CO₂
Estimate emissions from distance driven in a car.
Gallons of gas to CO₂
Turn fuel burned into kilograms of CO₂.
Natural gas therms to CO₂
Convert home heating gas use into emissions.
Flight vs train emissions
Compare the carbon cost of flying against taking the train.
EV vs petrol cost
Compare running costs and emissions of electric vs petrol cars.
Solar panel payback
Estimate savings and payback time for a solar install.
Numbers you can check
Emission factors come from published government and research data. Every calculator explains its inputs and assumptions, with source links wherever published data is used. No black boxes.
Published sources
Factors come from UK Government, US EPA and Ember datasets.
Shown, not hidden
Every calculator explains the factors and assumptions used in the result.
Linked & checkable
Published factors and datasets link back to their original sources.