Population Growth Rate Calculator

Calculate the annual population growth rate, projected future population, and doubling time using standard demographic models.

Initial Population (P₀)

Final Population (Pₜ)

Number of Years (t)

Years to Project Into Future (optional)

Results will appear here.

Formulas Used

Continuous Exponential Growth Rate:
r = ln(P_t / P₀) / t

CAGR (Compound Annual Growth Rate):
CAGR = (P_t / P₀)^1/t − 1

Future Population Projection:
P_future = P_t × e^{(r × t_future)}

Exact Doubling Time:
T_double = ln(2) / r ≈ 0.6931 / r

Rule of 70 (approximate doubling time):
T_double ≈ 70 / r%

Assumptions & References

Formula reference: Preston, S., Heuveline, P., & Guillot, M. (2001). Demography: Measuring and Modeling Population Processes. Blackwell.

Read Next

How to Get Help for Biology ANA › Life Services Authority Authority › Biology How to Get Help for Biology Biology has a way of feeling manageable right up until it doesn't —... Biology: Frequently Asked Questions ANA › Life Services Authority Authority › Biology Biology: Frequently Asked Questions Biology is one of those subjects that turns out to be far... Science: Frequently Asked Questions ANA › Life Services Authority Authority › Biology Science: Frequently Asked Questions Engaging with science — whether as a student, a researcher,...