Hardy–Weinberg: Recessive Phenotype Calculator
🧬 Genetics & evolution. Use the Hardy–Weinberg: recessive phenotype formula to find fraction with the recessive phenotype, q (recessive allele): pick the value you want, type the others, and the answer updates as you go.
Count the individuals showing the recessive trait, then take the square root to find q.
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| Fraction with the recessive phenotype | no unit |
| q (recessive allele) | no unit |
Worked example
Find the fraction with the recessive phenotype when q (recessive allele) = 0.7.
Using q² = frequency of the recessive phenotype: Fraction with the recessive phenotype = 0.49.
Frequently asked questions
What is the formula for Hardy–Weinberg: recessive phenotype?
q² = frequency of the recessive phenotype. Count the individuals showing the recessive trait, then take the square root to find q.
What do the letters stand for, and what units are used?
Fraction with the recessive phenotype, q (recessive allele).
How do you calculate fraction with the recessive phenotype?
Put the values into q² = frequency of the recessive phenotype. For example, with q (recessive allele) = 0.7, fraction with the recessive phenotype = 0.49.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (fraction with the recessive phenotype, q (recessive allele)) and fill in the others: it rearranges the formula for you.
