Tool
Personal Carbon Footprint Calculator
Estimate your annual carbon footprint from electricity, gas, car travel, flights, diet and waste, in kg CO2e per year.
Tools
Every tool calculates live in your browser, shows its formula and factors, and states its limits. No tool shows demo numbers.
Tool
Home Energy CO2 Estimator
Estimate annual CO2 from home electricity, natural gas, heating oil and LPG.
Tool
Temperature and CO2e Unit Converters
Convert Celsius, Fahrenheit and Kelvin, and convert kg, tonnes and pounds of CO2e.
Tool
Car Trip Emissions Estimator
Estimate CO2 for a car trip by distance, fuel type and consumption, with per-passenger figures.
Tool
Flight Emissions Estimator
Estimate flight CO2e by distance, cabin class, return/one-way and radiative-forcing toggle.
Frequently asked questions
What does the Personal Carbon Footprint Calculator estimate?
It estimates your annual carbon footprint in kilograms of CO2e per year from electricity, gas, car travel, flights, diet, and waste. It uses UK DEFRA 2024 factors for electricity, gas, petrol, and diesel, diet pattern averages from Poore and Nemecek (2018) via Our World in Data, and a landfill waste factor. Fuel factors are combustion-only, flights use economy factors with radiative forcing, and the result is an estimate, not a measured footprint.
What does the Home Energy CO2 Estimator cover?
It estimates annual CO2 from home electricity, natural gas, heating oil, and LPG using UK DEFRA 2024 factors. The factors are combustion-only, so the result is an estimate rather than a bill-accurate figure. If your home is outside the UK, replace the grid factor with your local verified factor.
What can the Temperature and CO2e Unit Converters do?
They convert between Celsius, Fahrenheit, and Kelvin, and between kilograms, tonnes, and pounds of CO2e. They use exact definitions only, with one tonne equal to 1,000 kilograms and one pound equal to 0.45359237 kilograms, and results are rounded to two decimal places. Kelvin below zero is rejected because it is physically impossible.
How does the Car Trip Emissions Estimator work?
It estimates CO2 for a car trip from distance, fuel type, and consumption, and it also gives per-passenger figures. Petrol and diesel use UK DEFRA 2024 combustion factors, while electric cars use the editable grid factor, which defaults to the UK figure. Vehicle manufacture, road, and well-to-tank emissions are excluded and stated in the tool.
How does the Flight Emissions Estimator work?
It estimates flight CO2e from distance, cabin class, whether the trip is return or one-way, and a radiative-forcing toggle. It uses UK DEFRA 2024 factors with and without radiative forcing, with higher cabin multipliers for business and first class. You must enter the distance yourself because no airport lookup is included, and results are estimates, not airline-reported emissions.
Can I use a tool result for carbon offsets, trading, or a bill?
No, the tools are for personal estimation only and their limitations say so directly. The footprint calculator must not be used as an offset or trading figure, and the home-energy result is an estimate, not a bill-accurate figure. For a non-UK home, replace the default UK grid factor with your local verified factor before treating any result as meaningful for your situation.