How to use the effective population size calculator
Find the effective population size from the number of breeding males and females. Enter breeding males, breeding females in the fields above; the effective population size, ratio to breeding population are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “effective population size”, “Ne formula”, “breeding males and females genetic drift”, “calculate effective population size”, “find effective population size”.
Formula
Variables
- Nm — Breeding males (individuals)
- Nf — Breeding females (individuals)
Worked example
With breeding males = 10 individuals, breeding females = 20 individuals, the calculator gives effective population size ≈ 26.66667 individuals; ratio to breeding population ≈ 88.88889 %.
Frequently asked questions
What is the effective population size calculator used for?
Find the effective population size from the number of breeding males and females. It helps with questions such as “effective population size”, “Ne formula”, “breeding males and females genetic drift”.
What is the formula for the effective population size calculation?
Effective population size (individuals) = 4 × Nm × Nf / (Nm+Nf). Ratio to breeding population (%) = [Effective population size] / (Nm+Nf) × 100. Here Nm is breeding males (individuals), Nf is breeding females (individuals).
What inputs do I need for the effective population size calculator?
You need breeding males in individuals, breeding females in individuals. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the effective population size calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the effective population size result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.