Carbon credits are one way that companies or individuals can reduce their impact on the environment. Rather than encouraging direct action, a carbon credit, or carbon offset, allows for the purchase of other carbon savings accrued from carbon development companies. Purchasing carbon credits may not directly reduce your personal carbon footprint, but it can go a long way toward encouraging companies to be more responsible. Determining your footprint is the first step in knowing how best to offset that output.

Write down the square footage of your house. Homes use varying amounts of carbon energy depending largely on the square footage. If your house is under 1,000 square feet, then write 10,000 next to the square footage. 10,000 is the number of pounds of carbon dioxide your house likely produces every year. For every additional 100 square feet of house, add 1,500 to the total CO2. For example, if your home is 1,800 square feet, then the carbon dioxide produced every year is likely around 22,000 lb.

Add up your total flight miles for a year and convert them into carbon expenditure. A good rule of thumb for flight-to-carbon conversion is 4 lb. of carbon for every 10 miles flown. Thus if you traveled 10,000 miles by plane, you will have used approximately 4,000 lb. of carbon.

Determine the carbon expenditure of your car based on the miles per gallon you achieve. For each hybrid you own add, 6,000 lb. to your total carbon tally. For cars with 20 to 40 mpg, add 10,000, and for cars with under 20 mpg add 20,000 lb. This number assumes you drive at the national average, approximately 12,000 miles per year.

Add an additional 10,000 lb. per person in your household. This number will in some way mitigate the carbon expenditure attendant with shipping and selling food.

Add up the total pounds of carbon expenditure. This should give you a complete sense of the pounds of CO2 emitted by your household's actions every year. Reducing or eliminating your total carbon footprint can be the first step toward a more responsible future.

Divide the total poundage of carbon expenditure by 2000. A standard carbon credit is purchased as a unit worth 1 ton of carbon expenditure.