How to Calculate Your Carbon Footprint with Online Calculators

With the climate crisis in full swing and experts predicting we have less than 10 years to stop the worst effects, it's time each of us take a good hard look at our carbon footprints (and those of our governments!).


A carbon footprint is calculated by estimating the amount of carbon emissions that are generated from specific activities, products, etc. It is reported in pounds of CO2 (carbon dioxide) even though not all items will produce CO2 as a carbon emission. Vehicles, for example, release a variety of noxious gases including methane, but the carbon footprint of driving a car is still report in relationship to pounds of carbon. This helps keep calculations uniform and helps us compare the impact of different actions.


Using An Online Calculator


Many online carbon footprint calculators exist to help you estimate your personal carbon footprint. It's important to recognize though that they are all estimates and will therefore vary dramatically depending on how you answer the questions. Without being a scientist yourself and without the capacity to analyze the life cycle of each one of the items you consume, it's nearly impossible to know your exact footprint.


These online calculators are primarily helpful not for knowing your exact carbon footprint, but rather for understanding what areas of your life could use the most work. They can also highlight how small changes in some areas might make a big difference in carbon emissions. Many calculators, for example, often ask about how fast you drive as miles per hour can impact your gas mileage. Reducing how much you speed can therefore reduce your car's carbon footprint - the more you know!


Results Vary So Take a Few


In preparation for this article, I went ahead and filled out seven carbon footprint calculators online. The results ranged from 5,900 pounds of carbon emissions per year to 17,000 pounds, showing a lack of consistency. What was consistent though across the calculators was the areas of my lifestyle that produced the most carbon: my home energy and transportation. Therefore, no matter the exact number calculated, efforts directed towards those areas would bring about the most change.


For this reason, go ahead and fill out a few different calculators to see how your results vary. You don't have to do six, but at least choose two! Then target those areas that come up as your largest footprint.


Seven Online Carbon Footprint Calculators


1. The Nature Conservancy: 11 tons / 22,000 pounds


According to the Nature Conservancy carbon footprint calculator, I am currently producing 11 tons of CO2 emissions every year. For the U.S., that means I am doing 59% better than the average footprint of my fellow citizens. The largest portion of my footprint comes from my home, because my rental does not have well insulated walls nor energy efficient appliances. Flying and driving also bring my footprint up quite a bit as I do home visiting for work and fly to visit relatives each year.


Nature Conservancy Carbon Footprint Calculator

2. EPA Carbon Footprint Calculator: 5.33 tons / 10,679 pounds


The Environmental Protection Agency calculated my carbon footprint at 10, 679 pounds, lower than the average U.S. footprint of 19,702 pounds. Again, the biggest areas were home energy and transportation in my footprint. The EPA though only reports on three categories of someones lifestyle: home energy, transportation, and waste. The results therefore felt very general as I was not asked questions about my diet nor purchasing habits.


Interestingly enough though, my results from the EPA were the smallest out of all seven calculators. That may either show the U.S.'s governments tendency to underestimate environmental impacts. Or may reflect how many carbon footprint calculators are run by carbon offset companies and may be inflated to promote purchasing carbon offsets...


EPA Carbon Footprint Calculator

3. My Personal Earth Overshoot Day: 5,900 pounds


Every year an organization calculates how many earths we need in order to survive at the current consumption rate worldwide. They also calculate the day in which we have used up all the resources our earth could feasibly generate within a year (called Earth Overshoot Day). The only reason we can continue consuming more resources is because the Earth has built up stock of these resources over its existence. But one day the extra will run out.


Based on my current carbon footprint and consumption rates, the Earth would not be able to sustain my lifestyle if everyone adopted it. In fact, I would need 1.8 Earths, a chilling number. By July 17th of each year, I would have consumed enough resources to begin outpacing the Earth's own production.


Earth Overshoot Day

4. World Wildlife Fund: 8.2 tonnes / 18,077 pounds


The World Wildlife Fund offers a carbon footprint calculator, specific to the United Kingdom. Calculators are different based on the country because your share of the governments' footprint is different as well. So theoretically, this calculator isn't really accurate for me but I wanted to test it out to report back.


Interestingly my food and stuff footprint was rather high for this calculator. Given that I purchase very few items new and eat a primarily plant-based diet, I wonder how accurate it is. As I prefaced above though, these are all estimates and can only be so accurate. The impact of my home energy still comes in as my largest footprint.


World Wildlife Fund Carbon Footprint Calculator

5. Cool Climate Carbon Footprint Calculator: 17 tons / 34,000 pounds


The Cool Climate Calculator was especially interesting to fill out because their results graph has more details and breakdowns. They also provide suggestions at the end of specific actions you can take and their CO2 equivalent reductions. Interestingly, many of the suggestions also save you money on a yearly basis, which the calculator gives you information about.


Cool Climate Carbon Footprint Calculator

6. Conservation Carbon Footprint Calculator: 14.01 tons / 28,020 pounds


The Conservation Carbon Footprint Calculator reports your final carbon footprint not only in tons but in "tree equivalents". Did you know that the average tree absorbs 0.07 tons of CO2 annually? That means I would need at least 200 new, mature, trees to be planted every year to off-set my emissions. Something that I definitely could not achieve on my own!


Conservation Carbon Footprint Calculator

7. TerraPass Carbon Footprint Calculator: 7.58 tons / 15,170 pounds


TerraPass offers a calculator for individuals, businesses, and for events, with the questions differing slightly. They don't provide a lovely graphic at the end and require you to put in your email to receive the complete report which is a little frustrating. The company though does have a pretty good rep as a trustworthy options for purchasing carbon offsets!


TerraPass Carbon Footprint Calculator

Have you calculated your carbon footprint before? Have you found it useful in implementing changes?