Ecological Footprint Calculator Formula
Understand the math behind the ecological footprint calculator. Each variable explained with a worked example.
Formulas Used
Total Ecological Footprint
total_footprint = food_gha + housing_gha + transport_gha + goods_ghaEarths Needed (if everyone lived like you)
earths_needed = (food_gha + housing_gha + transport_gha + goods_gha) / 1.6Variables
| Variable | Description | Default |
|---|---|---|
food_gha | Food Footprint(gha) | 1.2 |
housing_gha | Housing Footprint(gha) | 0.8 |
transport_gha | Transport Footprint(gha) | 1.5 |
goods_gha | Goods & Services Footprint(gha) | 1 |
How It Works
Ecological Footprint
Your ecological footprint is the total area of productive land and water needed to produce what you consume and absorb your waste, measured in global hectares (gha).
Formula
Total Footprint = Food + Housing + Transport + Goods (all in gha)
Earths Needed = Total Footprint / Biocapacity per person
The world has about 1.6 gha of biocapacity per person. The average American uses about 8 gha, meaning if everyone lived like an American, we would need 5 Earths.
Worked Example
A person with moderate consumption across four categories.
- 01Total = 1.2 + 0.8 + 1.5 + 1.0 = 4.5 gha
- 02Earths needed = 4.5 / 1.6 = 2.8 Earths
Frequently Asked Questions
What is a global hectare?
A global hectare (gha) is a productivity-weighted hectare used to measure ecological footprints. It accounts for different land productivities worldwide.
How many Earths are we currently using?
Humanity currently uses about 1.75 Earths worth of resources annually, meaning we consume more than the planet can regenerate in a year.
What has the biggest impact on my footprint?
For most people, transportation (especially flying) and food (especially meat) are the largest components. Housing energy and consumer goods follow.
Ready to run the numbers?
Open Ecological Footprint Calculator