Carbon Footprint Calculators: Round 1

Consumers these days are inundated with various carbon footprint calculators to determine their individual impact on this planet. Most of these calculators use some combination of data on one’s home energy decisions, transportation choices, and waste produced. And yet, counting carbon remains an incredibly complicated process.

As “the race to decarbonize” continues, there is an entire academic field working to establish standardized practices for carbon calculations. Assuming one is interested in understanding their secondary footprint (the emissions created by the manufacturing, production, transportation, and disposal of a product), there are a huge number of factors contributing to one’s emissions from a single product. Now, imagine trying to assess the entire contents of an individual’s life and to try to do it before losing their attention span. This is the challenge that the individuals building these calculators are faced with.

Though difficult to know for sure, most of these calculators seem relatively effective at ballparking one’s impact, bolstered by the disclaimer that one’s individual habits, precise location, and lifestyle choices are not accounted for in this calculation but do affect one’s individual carbon footprint.

As our team attempts to better understand SHIFT’s impact in terms of quantifying the amount of emissions avoided from the retirement of a personal vehicle, we have also begun exploring the tools freely available online to assess one’s personal emissions contributions.


First up, we have the MyClimate calculator, or rather calculators. This site has a calculator for individuals’ flights, car trips, and cruises; they also have options to measure emissions for companies and events. All are available freely except the company carbon footprint calculator.

The flight calculator is meant to show users how much carbon is produced from one individual trip. This organization’s distinguishing factor is their aim to map direct emissions during (in-flight fuel usage) but also indirect emissions from upstream and downstream processes. So what the user doesn’t see is that the production and transport of the airplane and its parts, the energy used to produce asphalt runways, and maintenance tasks are added into the calculations based on the user’s mileage in proportion to the full life cycle of an average passenger plane and all of the passengers it will transport through its operational lifetime. The same inclusion of emissions from upstream and downstream processes are accounted for in their car calculator as well, including vehicle disposal (yay!). 


These calculators give users the amount of CO2 their actions produce in tons. They then provide users with the opportunity to donate to various sustainable development projects, mostly abroad. Underneath the options to donate, one is greeted by a pretty dismal comparison of your calculated emissions to the maximum amount of CO2 that a single person would be able to generate in a year in order for climate change to “stop”.

The picture at right was the result of a single round trip ticket from NYC to Paris. That tiny blue bar (if we can even call it that) is what our target should be. It really shows how far off we are. MyClimate uses the same data sources and basic methodology across all of its different calculators.

For data MyClimate uses Ecoinvent, a life cycle inventory database that was created to support sustainability assessments. The data is available freely to individuals and for commercial licenses at a price. For methodology, MyClimate abides by the 2006 International Panel on Climate Change’s Guidelines on Reporting National Greenhouse Gas Inventories and its 2019 refinement, a document that was originally created so that “any country, regardless of experience or resources, should be able to produce reliable estimates of their emissions and removals of these gases.” (IPCC 2006). One thing to note is that this organization is based in Zurich and there is not an option to change your country on each calculator, save for the household calculator. Overall, this calculator is best for calculating emissions for stand-alone events, such as travel. 

Another widely used calculator is the EPA’s Household Carbon Footprint Calculator. Though one might expect this tool to be exceptional given it has the backing of the United States’ federal government, one would be disappointed. This calculator includes very little; questions regarding flights, food preferences, or shopping habits are noticeably absent. The calculator focuses heavily on home energy and car usage but stops there. Some have found this calculator to be greatly underestimating one’s impact. One thing this calculator does well is offer practical ways to reduce one’s emissions, including the cost of implementation and the amount of lbs of CO2 saved annually from each reduction strategy.


Next up, The Footprint Calculator. This carbon footprint calculator is run by an international nonprofit dedicated to ending ‘Ecological Overshoot’, otherwise described as the use of resources of an amount exceeding the Earth’s ability to renew in an entire year. The Footprint Calculator’s calculator calculates individuals personal Earth overshoot day. This is the date that, if everyone lived like you, Earth’s population would have used as many as earth’s resources as it can renew in an entire year. My Earth overshoot day was in March. Yikes.

This site is notably pleasant, outfitted with dynamic graphics and a simple, smooth click to get to the next question. The calculator is quick to use; it asks users 13 questions that require one to rank their answer along a sliding scale of 0% to 100%. The questions might be as follows: What percentage of your home’s electricity comes from renewable sources? Interestingly, the calculator allows users to select the option to “Add details to improve accuracy” where there are two additional questions that elaborate on what was originally asked. This custom-fit way of making a calculator allows the site to target users that want a quick, topical view of their emissions in addition to users that are prioritizing accuracy over speed. 


One downside of this site is that its results are not easily comparable, or really even practical beyond the scope of itself. With this said, this is the only calculator that is really geared towards biocapacity as opposed to emissions outright. As their site states, “The Ecological Footprint is derived by tracking how much biologically productive area it takes to provide for all the competing demands of people.”. Based on the National Footprint and Biocapacity Accounts (NFAs) maintained by York University and calculated using UN affiliated data sets, their methodology is transparent and thorough. Bonus points for their commitment to encouraging the public to explore open data sets. Extra bonus points for servicing 200+ countries as well. 


Lastly, CoolClimate, a partnership between various actors run out of University of California Berkeley. The CoolClimate network claims to have “developed the first carbon footprint calculators to account for the greenhouse gas emissions of all transportation, energy, food, goods and services purchased by households and businesses.”, a method they classify as “consumption-based greenhouse gas accounting”. This aspect, along with the fact that this calculator was created using exclusively US data is what distinguishes it from the others.


The user begins by plugging in their postal code, number of household residents, and annual household income. One then moves through the tabs: transport (cars, flights, public transport) home (home energy and water usage, living space), food (consumption of grains, dairy, animal products), and shopping (divided into goods and services). The last 2 categories have the option to go through an advanced version asking for more information.

At the end of the tabs the user lands on a final one called ‘Take Action’. This tab gives users a personalized list of ways to reduce one’s impact with the chance to pledge to do one or more tasks from the list. The site gamifies reduction efforts by also having a leaderboard ranked by CO2eq/year and amount of pledges committed to (captured left).

As a US resident this seems to be one of the best options for consumers. Plus, by supporting this project you are supporting a network that doesn’t stop at making decision-making tools for consumers, but also is working to accelerate the transition to clean energy at the neighborhood, city, state, and national level.


What these calculators have in common are some fundamental problems that cannot be avoided; since they cannot inquire about every nitty-gritty detail of the user’s life, they rely on certain assumptions. There are also problems due to the nature of self-reporting and the biases that this form of data collection comes with. As a result, there is an interest in developing a carbon footprint calculator that veers from the consumer-questionnaire format entirely, thereby avoiding the inaccuracies created by self reporting and the assumptions that allow these calculators to work. For example, this study suggests that one’s financial transaction data could be used to determine one’s carbon footprint.

There are a slew of other tools and consulting companies that do this type of carbon calculating for businesses as well. They are a different category in themselves as they aren’t built to appeal to the everyday consumer interested in their impact. Still, these same issues of not being able to account for every aspect and having to rely on averages or build broad categories exist.


This blog is a series of three posts in which we break down and review the different carbon calculators available freely to consumers. We’ve only begun to scratch the surface. Round 2 will be released next week.