Carbon dioxide emission calculator

This carbon dioxide emission calculator will help you gain an approximate idea of how many tons of carbon dioxide some of your activities generate and how many trees it would take to offset those emissions.

Calculator usage instructions

  • Enter the appropriate figures into the quantity column - all fields are optional.
  • The number of tons of CO2 will be displayed in the other column.
  • At the bottom of the form, the total amount of carbon dioxide emissions will be displayed as an annual and monthly figure and also the number of trees needed to offset. Explanatory notes are below.
Total Tons of CO2 annually
Small car
(40 mpg fuel economy)

miles per month

Average/medium car
(21 mpg fuel economy)

miles per month

SUV/4 wheel drive
(15 mpg fuel economy)

miles per month

Home electricity use


Natural/propane gas

cubic feet/month

Fuel oil heating

gallons per month

Air Travel

miles per month

Train Travel

miles per month

General waste - how many people in your household?

no. of people

How many people in your household have meat in their diet?

no. of people

Total monthly emissions tons  
Total annual emissions tons  
No. of trees to offset trees

Notes on CO2 emissions calculator: 

The calculator is not designed to be 100% accurate as there are too many variables required in order to give a reliable emissions total. It is simply to give you an indication on how much carbon dioxide you generate. Bear in mind that just about all we do in modern life produces a carbon footprint, well over and above what occurs in the natural world. For instance, the computer you are viewing this on was produced using processes that create carbon emissions.

The calculations are based on the following:

  • Household electricity is based on a figure of 0.68 kilograms of carbon emissions per kilowatt hour
    generated by a coal fired power station.
  • Natural gas emissions calculated on 0.054 kilograms of carbon dioxide per cubic foot.
  • Fuel oil based on 10.11 kilograms CO2 emissions per gallon.
  • Small car emissions calculated on 0.26 kilograms emissions per passenger, per mile.
  • Medium car emissions calculations based on pounds of carbon dioxide emissions per mile.
  • SUV/4 wheel drive carbon dioxide emissions based on pounds per mile.
  • Air travel emissions based on Boeing 747 at average capacity and calculated per person.
  • Train travel calculations based on average occupancy of intercity train.
  • Tree calculation is based on an average tree removing 149 kilograms of carbon dioxide annually. Note that the tree may take many years to grow to achieve this rate and is dependent upon species. I've also factored in a 25% mortality/productivity rate; i.e. that 25% of trees planted won't reach the age to process this amount of carbon dioxide or be compromised in some way so that they only process 75% of that amount.
  • General waste is based on the average carbon dioxide emission equivalent of 458 kilograms per person per year. If your household recycles glass, paper, plastic and cans; only enter in half the number of people in your household for a more accurate figure.