CO₂ Emission Calculator

Annual CO₂ footprint from driving, electricity, cooking gas and flights, with tree offset.

What it does

Adds up the CO₂ from driving, electricity, cooking gas and flights into a yearly footprint, and shows how many trees would offset it.

Where it's used

Understanding your personal or household carbon footprint.

How to use it

  1. Choose whether you enter monthly or yearly values.
  2. Enter driving distance, fuel and mileage.
  3. Enter electricity, LPG / gas use and flight hours.
  4. Set your grid’s CO₂ factor if you know it.

The formula explained

Petrol
≈ 2.31 kg CO₂ per litre
Diesel
≈ 2.68 kg CO₂ per litre
LPG
≈ 2.98 kg CO₂ per kg
Grid factor
kg CO₂ per kWh — varies by country

Worked example

Inputs:

The calculator gives:

Tips and common mistakes

Questions people ask

What emission factors are used?

About 2.31 kg of CO₂ per litre of petrol, 2.68 kg per litre of diesel and about 3 kg per kg of LPG, plus your grid’s figure per kWh of electricity. The example works out at about 479 kg a month.

How many trees offset a tonne of CO₂?

The calculator assumes a growing tree takes up roughly 22 kg of CO₂ a year, so about 46 trees per tonne per year. Real figures vary widely with species, age and climate.

Where should I start cutting?

With the biggest share. In the example, driving and electricity are almost equal at about 220 kg a month each, so a more efficient car, fewer kilometres or solar panels would each make a real difference.

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