Enter your Initial Population (P₀), Growth Rate (r), Time Period (t), and Time Unit into the Exponential Population Growth Calculator to find your Final Population, along with the Population Change, Percent Change, and how long until the population doubles (Doubling Time).
Final Population
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Population Change
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Percent Change
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Doubling Time
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Use the formula P(t) = P₀ × (1 + r/100)^t, where P₀ is initial population, r is growth rate percentage, and t is time period. This shows how populations grow at a constant rate over time.
Linear growth increases by a constant amount each period, while exponential growth increases by a constant percentage. Exponential growth starts slowly but accelerates dramatically over time.
Yes, negative growth rates represent population decline or decay. The rate should be between -100% and any positive value, as a decline of more than 100% would result in negative population.
Exponential growth models apply to bacteria colonies, human populations, radioactive decay, compound interest, viral spread, and many biological and economic processes.
Doubling time = ln(2) / ln(1 + r/100), where r is the growth rate percentage. This tells you how long it takes for a population to double at the current growth rate.
Mathematically yes, negative time represents past populations. If t = -5, you're calculating what the population was 5 time units ago based on current growth patterns.
A growth rate of 0% means no change - the population remains constant at the initial value regardless of time period. The formula becomes P(t) = P₀.