Ecological Footprint Calculator
An ecological footprint adds up the biologically productive area, in global hectares, needed to supply what you consume and absorb your waste, then compares it with the biocapacity available per person. This calculator sums the footprint you supply for four consumption categories (carbon, food, housing, and goods and services) into a total per-person footprint, then divides by the available biocapacity per person to give the number of Earths that level of living would require. Because real category footprints come from detailed, country-specific conversion factors published by accounting bodies such as the Global Footprint Network, each value is a user-editable input so nothing is fabricated.
Ecological footprint formula
Total footprint = carbon + food + housing + goods
Number of Earths = total footprint / biocapacity per person
Overshoot = total footprint - biocapacity per person
Footprint vs biocapacity = total footprint / biocapacity * 100
All footprints and biocapacity are in global hectares (gha). A number of Earths above one indicates the modelled consumption exceeds the biocapacity you entered.
Footprint accounting context
- A global hectare is one hectare with world-average biological productivity.
- The carbon component is usually the largest share for high-income lifestyles.
- Overshoot means consumption exceeds the regenerative capacity you compared against.
- Category footprints depend on country-specific conversion factors, so they are inputs here.
- The Global Footprint Network publishes the National Footprint and Biocapacity Accounts.
Ecological footprint: frequently asked questions
What is an ecological footprint?
An ecological footprint measures the biologically productive land and sea area required to supply what a population consumes and to absorb its waste, expressed in global hectares (gha). One global hectare is one hectare of land with world-average biological productivity. This calculator sums the footprint you supply for each consumption category.
What is biocapacity?
Biocapacity is the productive capacity of an area to regenerate resources and absorb waste, also measured in global hectares. When total footprint exceeds available biocapacity, consumption is in ecological overshoot. You enter the biocapacity per person you want to compare against, so the figure stays sourced rather than assumed.
How is the number of Earths calculated?
Divide the total footprint per person by the available biocapacity per person. If everyone lived at a footprint equal to twice the available biocapacity, it would take two Earths to sustain that level. The ratio is a vivid way to communicate overshoot.
Why are the category values inputs rather than fixed?
A genuine footprint depends on detailed lifestyle data and conversion factors that vary by country and year, published by bodies such as the Global Footprint Network. To avoid inventing figures, the calculator takes each category footprint in global hectares as a user-editable input you can fill from an audited source.
What does global overshoot mean?
Global overshoot occurs when humanity's total footprint exceeds the planet's total biocapacity in a year, meaning resources are drawn down faster than ecosystems regenerate them. A number of Earths greater than one indicates the modelled level of consumption is not sustainable.
Official sources
- Global Footprint Network: ecological footprint and biocapacity accounts.
- U.S. Environmental Protection Agency: EnviroAtlas ecosystem data.
Reviewed by the CalculatorHub team, edited by James Graham, 17 June 2026. See our methodology.