What is Household Carbon Calculator?
Household Carbon Calculator helps you estimate a household's annual emissions using energy consumption and entered factors.
The main result is estimated annual footprint, with a breakdown of monthly footprint. The formula, example and assumptions below explain how to interpret it.
How to use Household Carbon Calculator
Use the example to get familiar with the form, then enter your own figures. Any rates in the example are illustrative. Check the field labels and units before calculating.
- Gather monthly electricity (kWh), electricity emissions factor (kg CO₂e/kWh), monthly petrol consumption (litres), petrol emissions factor (kg CO₂/litre) and other monthly emissions (kg CO₂e). Use values from the same situation or reporting period.
- Replace the example monthly electricity with your own value, then complete the other fields. Check the displayed units.
- Select Calculate and read estimated annual footprint with its result breakdown. Change one input and calculate again to compare a second scenario. Reset restores the original example.
- Enter monthly electricity in kWh, at least 0. Decimals are accepted.
- Enter electricity emissions factor in kg CO₂e/kWh, at least 0. Decimals are accepted.
- Enter monthly petrol consumption in litres, at least 0. Decimals are accepted.
- Enter petrol emissions factor in kg CO₂/litre, at least 0. Decimals are accepted.
- Enter other monthly emissions in kg CO₂e, at least 0. Decimals are accepted.
Household Carbon Calculator: a worked example
With the inputs below, the result is 3.486 tonnes CO₂e (estimated annual footprint). Follow the example, then replace these illustrative values with your own.
| Input or output | Example value |
|---|---|
| Monthly electricity (kWh) | 250 kWh |
| Electricity emissions factor (kg CO₂e/kWh) | 0.7 kg CO₂e/kWh |
| Monthly petrol consumption (litres) | 50 litres |
| Petrol emissions factor (kg CO₂/litre) | 2.31 kg CO₂/litre |
| Other monthly emissions (kg CO₂e) | 0 kg CO₂e |
| Estimated annual footprint | 3.486 tonnes CO₂e |
| Monthly footprint | 290.5 kg CO₂e |
Understanding the Household Carbon result
Read estimated annual footprint alongside monthly footprint. These describe different parts of the same calculation.
Displayed results use a readable number of decimal places. When checking a result by hand, keep extra precision until the last step. To compare scenarios, change one input at a time and keep the others fixed.
- Example Monthly footprint: 290.5 kg CO₂e
Household Carbon Calculator: assumptions and common mistakes
A useful estimate starts with the right inputs. Check the following assumptions and limits before applying the result to your situation.
- Example factors are editable. Use verified factors for your grid, period and reporting boundary; vehicle manufacture and other unentered sources are excluded.
- Match factors to your location and reporting period. A result covers the sources you entered, not an independently verified full footprint.
For wider guidance, visit GHG Protocol calculation guidance. The formula and scope of this specific tool are stated on this page.
