How to use the allele frequency calculator
Find allele frequencies from genotype counts. Enter aa individuals, aa individuals, aa individuals in the fields above; the frequency of a, frequency of a are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- AA — AA individuals
- Aa — Aa individuals
- aa — aa individuals
Worked example
With aa individuals = 40, aa individuals = 40, aa individuals = 20, the calculator gives frequency of a ≈ 0.6; frequency of a ≈ 0.4.
Frequently asked questions
What is the formula for the allele frequency calculation?
Frequency of A = (2 × AA+Aa) / (2 × (AA+Aa+aa)). Frequency of a = 1-[Frequency of A]. Here AA is aa individuals, Aa is aa individuals, aa is aa individuals.
What inputs do I need for the allele frequency calculator?
You need aa individuals, aa individuals, aa 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 this 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 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.