Ecology Calculators

Bioaccumulation Factor Calculator

Calculate the Bioaccumulation Factor (BAF) comparing a substance's concentration in an organism versus its surrounding environment.

Biomagnification Factor Calculator

Calculate the Biomagnification Factor (BMF) showing how contaminant concentration changes from prey to predator in a food chain.

Carbon Sequestration Rate Calculator

Estimate total CO2 sequestered by trees over time based on tree count, absorption rate per tree, and number of years.

Carrying Capacity Calculator

Calculate an ecosystem's carrying capacity (K) - the maximum sustainable population size given available resources.

Habitat Edge-to-Area Ratio Calculator

Calculate the edge-to-area ratio of a habitat patch to assess fragmentation and available core habitat.

Litter Decomposition Rate Calculator

Calculate the percentage of leaf litter or organic matter remaining after a given time using the exponential decomposition model.

Logistic Population Growth Calculator

Calculate population size over time using the logistic growth model, which accounts for a fixed environmental carrying capacity.

Minimum Viable Population Calculator

Estimate the minimum census population needed for long-term species survival based on effective population size targets.

Net Primary Productivity Calculator

Calculate net primary productivity (NPP) by subtracting respiration from gross primary productivity (GPP).

Population Doubling Time Calculator

Calculate how long it takes a population growing at a constant rate to double in size, using the exact natural-log formula.

Population Growth Rate Calculator

Calculate future population size using the exponential growth model from initial population, growth rate, and time.

Predator-Prey Ratio Calculator

Calculate the prey-to-predator ratio in an ecosystem from prey and predator population counts.

Shannon Diversity Index Calculator

Calculate the Shannon Diversity Index (H) from species abundance data to measure biodiversity in an ecological community.

Simpson's Diversity Index Calculator

Calculate Simpson's Diversity Index (D) from species abundance data, the probability two random individuals belong to different species.

Species Evenness Calculator (Pielou's J)

Calculate Pielou's Evenness Index (J) from species abundance counts to measure how equally distributed a community is.

Species Richness Index Calculator

Calculate species richness using Margalef's Index, which normalizes species count by sample size.

Species-Area Relationship Calculator

Predict species count from habitat area using the classic species-area relationship (S = cA^z) from island biogeography theory.

Trophic Energy Transfer Calculator

Calculate how much energy remains after passing through multiple trophic levels using the 10% ecological transfer rule.

Water Footprint Calculator

Calculate your total water footprint combining direct water use with virtual water embedded in food and manufactured goods.

Water Use Efficiency Calculator

Calculate a plant's water use efficiency (WUE) as grams of biomass produced per liter of water transpired.

Populations Do Not Grow Forever

Real populations, unlike a purely exponential model, eventually run into limits — food, space, predators — that slow growth as the population approaches what an environment can actually sustain. These ten calculators cover the population, diversity, and energy-flow math ecologists use to describe that behavior.

The Logistic Growth Curve

Logistic population growth approaching a carrying capacity of 1,000 Starting population of 10 grows slowly, then rapidly, then levels off as it approaches the carrying capacity of 1,000. Carrying capacity (K) Time →
Logistic growth: population expands quickly at first, then growth slows as resources become limiting, leveling off near the carrying capacity. Modeled with the Logistic Population Growth Calculator.

An unlimited exponential model would keep curving upward forever; the logistic model instead bends toward a ceiling — the carrying capacity — as competition for resources intensifies. Model your own population with the Logistic Population Growth Calculator.

Popular Ecology Calculators

  • Shannon Diversity Index Calculator — quantifies species diversity in a community, accounting for both richness and evenness.
  • Trophic Energy Transfer Calculator — estimates energy passed between feeding levels, typically only about 10% per level.
  • Predator-Prey Ratio Calculator — evaluates whether a predator population is sustainable relative to its prey base.

Interested in the population math itself, not just the ecology application? See the Biology Calculators, or check land-use planning in Environmental Calculators.