Cotap’s CO2 calculator focuses on U.S. Residents and the major sources of their annual emissions – car travel, air travel, and home energy use. You should be able to complete it in 10 minutes or less.
You are welcome to calculate part or all of your footprint elsewhere, and to override one or more categories in the calculator’s ‘Total’ section by selecting ‘I want to enter my own value’ before matching your tonnes with one or more of our projects.
Results are in metric tons, also referred to as tonnes, which are 2,205 pounds.
Burning one gallon of gasoline emits 19.4 pounds of CO2 into the atmosphere, and one gallon of diesel emits 22.2 pounds (U.S. Environmental Protection Agency).
Example (gasoline): 12,000 miles per year ÷ 30 miles per gallon average = 400 gallons. 400 gallons x 19.4 pounds per gallon = 7,760 pounds ÷ 2,205 pounds per tonne = 3.52 tonnes.
Currently, our calculator only allows for two cars. If you have more cars, you’ll need to combine the miles and average the mileage figures for one of the cars.
Formula for a given round trip: (Round Trip Miles x Emissions Factor x Radiative Forcing Index Factor) ÷ 2,205 lbs per tonne = tonnes per round trip.
Example formula for a medium round trip flight: (2,000 miles x .371 lbs CO2 per mile x 1.9 RFI) ÷ 2,205 lbs per ton = .639 tonnes per flight.
Radiative Forcing Index (RFI). CO2 emissions from air travel have a greater effect on climate change because they are released directly into the upper atmosphere, instead of at lower elevations.
If you like, you can fine-tune your air travel footprint by using decimals. For example, for a 3,000-mile roundtrip flight you can input 1.5 in the “Medium” flights field.
Technical note: For home energy calculations, our calculator can only handle one method at a time. If you start using the Average method and decide to switch to the Actual method, you’ll need to reset the Averages’ State/Heating Type inputs to ‘Select,’ and vice versa.
Electricity formula (general): Your state’s CO2 lbs per kilowatt-hour (kWh) emissions rate x your state’s average residential kwh’s. The U.S. EPA publishes state electricity CO2 lbs per kWh, which is important to use because state emissions per kWh vary greatly due to how the electricity is generated (nuclear, coal, renewables, etc.). We also use the U.S. Energy Information Administration’s (EIA) data on average electricity consumption by state, because your region can heavily affect how much electricity you use for heating and/or air conditioning.
Heating Oil. Household average for U.S. using heating oil as the primary heating source. Based on 2009 U.S. residential consumption of 4.02 billion gallons for home heating oil (Distillate No.2), divided by 8 million households, equals 503 gallons/household per year, which is then multiplied by 22.33 lbs CO2 per gallon, then divided by 2,205 lbs per tonne to get 5.09 tonnes of CO2 per year emitted by the average U.S. heating oil household.
Cotap’s average method for your home energy footprint generates accurate results in most situations. However, if you have an uncommon region/heating type combination, an inaccurate total will likely result because there is no available data on residential heating oil and propane consumption by state.
As an example, if you live in Hawaii and happen to heat your home with heating oil (which is unlikely), then the Cotap calculator will still add 5.09 tonnes to your household total, but that 5.09 tonnes will be inaccurate because most heating oil customers are located in the Northeast region of the U.S., where the winters are much colder than in Hawaii.
If you disagree with your home energy footprint calculation using this method, please know that you are able to override it (with a number you prefer and/or calculator elsewhere) on the totals page prior to matching your CO2 footprint with one of our projects.
You’ll need access to your utility bills and/or your online utility account for this method.
For the most part, the above methods and logic are applied (i.e. CO2 lbs per kWh for your state, CO2 lbs per cubic foot of natural gas, and CO2 lbs per gallon of heating oil or natural gas.
The main difference is that you enter your actual kWh consumption and heating fuel usage (if not electricity) for the past 12 months.
For natural gas, the EIA reports consumption in cubic feet. Most people are billed in therms or “CCF”, which means hundred cubic feet. Cotap’s calculator is set up for therms. One therm = 1.03 CCF. If you are billed in CCF’s, multiply your annual total by 1.03 to get therms and thus ensure the highest level of accuracy.
Cotap focuses on the major sources of your carbon footprint: car travel, air travel, and home energy use.
If you would like to refine your CO2 footprint by accounting for categories like diet, pets, buying local, recycling, etc. you may adjust your total before checking out with us. If you feel strongly about us making this a formal part of our calculator, please send us feedback (instructions on that below).
Non-U.S. residents and using CO2 footprints calculated elsewhere
If you prefer a calculator from another website, you are more than welcome to generate your CO2 footprint figure there and then overwrite your total tonnes on Cotap before checking out through us.
Figures generated by Cotap’s calculator are metric tons, also referred to as ‘tonnes” (2,205 pounds), not short tons (2,000 pounds). If you calculate your footprint elsewhere in short tons, convert it by dividing by 1.1 (which is 2,205 ÷ 2,000) before checking out through us. Similarly, if you calculate it in pounds, divide by 2,205.
Offset Your CO2 and Change Lives »
$9.90/tonne | 90.9% to Projects | Tax-deductible (U.S.)
Testimonials & Beneficiary Profiles
"1000% Better. Stunned."
"I searched for hours to find a quality carbon offsetting site for individuals. Now that I have found COTAP I'm stunned. This is 1000% better than I dared hope for - for the quality of results you chase, for the wonderful projects you support, for the brilliant information about your projects, and for your accessible ways for individuals to purchase offsets. I've encouraged my friends to use you too. Thanks for all that you do!"David Rosenfeld London, United Kingdom
"An Awesome Organization"
"COTAP is an awesome organization and we use them to offset our entire company's carbon emissions every year! They do great work and also help alleviate poverty, I couldn't be more proud of them."Ben Welch-Bolen CEO, World Wide Web Hosting Fayetteville, Arkansas
"Increasing My Impact"
"The issue of global inequality and poverty in the developing world is truly one of the greatest challenges facing humanity today. At the same time, the impact that people are having on our environment threatens the longevity not just of humankind, but of our planet. COTAP empowers me to magnify my impact by addressing both issues at the same time."Louis Perwien Washington, D.C.
"Real, Measurable Change On Two Fronts"
"COTAP empowers me to make positive change in multiple communities around the world while counteracting my contribution to the long-term, ‘macro’ problem of climate change. It's real, measurable change on two fronts, and that makes COTAP very innovative and unique. COTAP's the wave of the future and I want to see it grow to reach more donors and communities."Shay O'Reilly Oakland, California
"A Simple, Effective Solution"
"COTAP is the solution for my carbon footprint that I can't erase on my own. Their process couldn't be more simple, and not only am I able to offset my carbon footprint, I am having a direct, positive, measurable impact on reducing poverty. What more could I ask for?"Paige Hamack Seattle, Washington
"Big Up to COTAP"
"The North American leg of the #FLYRASTA tour will start soon. Big up to Carbon Offsets To Alleviate Poverty (COTAP) for helping us offset our carbon footprint while we're on the road. We still have to do more. #ThankMotherEarth"Ziggy Marley Grammy Winning Musician Earth More at COTAP.org/Ziggy.
"A great way to do the right thing."
"Climate change and poverty are daunting challenges and COTAP is a great way to have a meaningful, measurable impact on both. The IPCC report states that we need to get to 600 lbs/CO2/person/year to keep warming under two degrees. So, I'm taking action towards becoming carbon neutral by driving an electric car, flying less, and offsetting my CO2 to address what I'm unable to eliminate. I choose COTAP because it's more meaningful, transparent, simple, and fun... and because it's a great investment in future generations!"Matt Hollingsworth Microsoft Technical Specialist Santa Monica, CA
"Truly unique and innovative."
"COTAP is the only organization that I’m aware of that directly connects the climate change and global poverty issues. It is a truly unique and innovative platform."Ted H. San Francisco, CA
Anastazia Solomon Country: Malawi Village: Mkokamwendo Trees Planted: 467 over 1 ha & 800-meters boundary plantings Climate Benefit: 193 tonnes of CO2 Earnings To Date: $360 Total Expected Earnings: $600 Livelihood Benefits: Children's school fees, home improvements, pig farming
Beatrice Ahimbisibwe Country: Uganda Community: Bitereko Trees Planted: 1,400 Total Earnings To Date: $1,831 Livelihood Benefits: New house, furniture, children's school fees, invested in building a new school
Maria Elisa Gonzales Country: Nicaragua Community: La Grecia Trees Planted: 3,167 Total Earnings To Date: $754.22 Total Expected Earnings: $2,026.69 Livelihood Benefits: Food, clothing, children's school supplies
Marcelino Arostegui Mendosa Country: Nicaragua Community: Morcillo Trees Planted: 2,917 Total Earnings To Date: $446.24 Total Expected Earnings: $1,711.13 Livelihood Benefits: Tools for farm repairs, extra food and supplies, fuelwood
"COTAP's about way more than climate change and carbon offsetting, because they address economic inequality too. They're more global, transparent, and accountable than other offset providers, and most charities in general. They're a refreshingly positive antidote to the always-negative and disempowering national climate conversation. COTAP's also compelling because they properly contextualize themselves with regards to the need for footprint reduction, and how they fit in with California's progressive policies like the Climate Credit and the Low Carbon Fuel Standard."Josh Chesler Long Beach, CA
"Great program for those that care about a livable world that we are borrowing from our kids and grandkids."Tim Reckmeyer Microsoft Technical Account Manager Minneapolis, MN
"Cooler Than Gangnam Style!"
"Your testimonial goes here! We're looking for existing customers to submit 50-100 word testimonials (this one is 82 words) sharing things like why you've offset your emissions with us, what you like about COTAP, and how you think we're different, better, etc. Testimonials are an effective and proven selling tool, and yours will help us convince more new visitors to our site that they, like you, should do their part about climate change while also improving incomes for the world's poorest people!"You Submit your testimonial at COTAP.org/Testimonials
Musingo Mikhaya Country: Uganda Village: Bukusu Trees Planted: 330 Climate Benefit: 178.4 tonnes of CO2 Earnings To Date: $142 Total Expected Earnings: $472 Livelihood Benefits: Healthcare costs, children's school fees, supported livestock farming, transport of farm produce to markets
Dorothy Nthala Country: Malawi Village: Tchale Trees Planted: 600 over 1800-meters boundary plantings Climate Benefit: 147 tonnes of CO2 Earnings To Date: $381 Total Expected Earnings: $685 Livelihood Benefits: Corrugated iron roof for her house, improved soil fertility, fuel wood, poles for tobacco curing sheds
Daniel Mukhwana Country: Uganda Village: Bumbo Trees Planted: 799 via dispersed interplantings over 4 hectares Climate Benefit: 475.6 tonnes of CO2 Earnings To Date: $378 Total Expected Earnings: $1260 Livelihood Benefits: Children's school fees, improved soil quality, shade for coffee crop
"COTAP's model is unique in that it recognizes the link between poverty and climate change and allows individuals to offset their carbon footprint whilst supporting projects that use innovative ways to build sustainable livelihoods for their communities."Eva Schoof Edinburgh, UK