# How to calculate the cost of a carbon offset

Offsetting my annual carbon footprint

For the purposes of the exercise, let's assume a hypothetical carbon footprint (determined by using our calculator). of 10,000 Kg.

• The calculation is 10,000(kg)/1,000(kg per tonne) = 10 tonnes.

• 10 tonnes x \$25 = \$250 per annum to offset your footprint.

Offsetting a flight

We use a figure of 0.1kg of carbon per km per passenger

A return flight from Auckland to Sydney for one passenger would require an offset of \$10.33 calculated as follows:  ​

• Calculate the distance between the cities at this link: https://www.distancefromto.net/

• The distance to Sydney is 2,156km x 2 (return flight) = 4,312km

• The carbon emissions are calculated as follows 4,132km x 0.1kg per km = 413.2kg

• 413.2kg x \$25per tonne = 413.2/1,000 x \$25 = \$10.33 to offset the flight.

Offsetting a Motor Vehicle Trip

We estimate that in a medium sized vehicle you will emit 0.24kg per kilometre.

• Using this, a one way trip between Kerikeri and Auckland (242km) would generate 58.08kg of carbon.

• 58.08kg/1,000 x \$25 = \$1.45 to offset the trip.