Calculation of personal footprint

Get an individual footprint in kilograms of CO2-equivalents from household information and habits. This can be used to build your own climate calculator with as many inputs as you'd like.

All inputs, outputs and defaults can be seen in the Calculate general technical API docs.


This endpoint receives:

  • a data source to base calculations on
  • a list of habits and a household description (specific questions are defined under different categories, as explained in the chapter on calculations)
  • the date for which the footprint should be computed

All inputs are optional and missing values are defaulted. If no input date is given, the current date is used as default. If no habits or household info are provided the calculation will assume default answers, i.e. that the user is similar to an average person from the data source you have specified. This can be used to compare a person's climate footprint to the average footprint for a country. 

The more questions a user answers, the better we understand a user’s behaviour, giving a more accurate footprint estimation. However some habits and behaviours have a greater influence on your climate footprint than others. You’d be right to assume that renovating your house is more impactful than buying an energy efficient washing machine. But what influences a person’s footprint the most? We’ve performed a sensitivity analysis to determine the top questions:

  • How many people reside in the household?
  • What type of house do you live in?
  • What is the indoor temperature set to inside your house?
  • What is the area (square metres) of the house you live in?
  • How often do you buy ethical and environmentally friendly goods?
  • What is your monthly household income after tax?


This endpoint returns a breakdown of an annual footprint in kilos of CO2e, with absolute and percentage values, in categories and subcategories.

If you have not submitted optional information, the footprint of an average person for the chosen data source will be returned.


Your personal climate footprint can be attributed to five major causes: food consumption, transportation use, energy consumption, purchase of goods and services, and your share of public expenditures. Personal habits and behaviours have a paramount impact on one’s climate footprint (for eg. the footprint of a person having a vegan diet will be much lower than the footprint of a person who eats meat frequently). We ask the user several questions in order to better identify their habits and behaviours, which enable us to estimate the footprint more accurately. The final footprint in each category is modified according to the habits of the user.

The input date also affects the calculations. We account for technology changes over time (more efficient food production, higher share of electric vehicles in the total vehicle fleet, greener electricity mix)  and seasonal changes (higher energy prices and emissions intensity in winter) and their impact on your footprint. For example, the emissions intensity of an average car five years ago was much higher than the emissions intensity today. Hence, the footprint of a journey taken five years ago would be much higher than the footprint of a journey taken today.

The calculations for each category are explained in the sections below. The footprint values of each category are aggregated to give an individual’s overall footprint.