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Calcimator

Punnett Square Generator

Calculate offspring genotype and phenotype ratios from parent genotypes using a Punnett square for monohybrid crosses.

Inputs

Results

AA Probability

25%

Aa Probability

50%

aa Probability

25%

Phenotype Ratio

3:1

Parent 1 GenotypeAa
Parent 2 GenotypeAa
Dominant Phenotype75%
Recessive Phenotype25%
How to Use This Calculator
  1. Enter Parent 1 Dominant Alleles and Parent 2 Dominant Alleles.
  2. Review AA Probability (%), Aa Probability (%), and aa Probability (%).
  3. Use Parent 1 Genotype and Parent 2 Genotype to inform your decision.
  4. Use the chart to visualize the results and explore different scenarios by adjusting inputs.

What each input means

Parent 1 Dominant Alleles
Number of dominant alleles for Parent 1: 0 = aa (homozygous recessive), 1 = Aa (heterozygous), 2 = AA (homozygous dominant).
Parent 2 Dominant Alleles
Number of dominant alleles for Parent 2: 0 = aa, 1 = Aa, 2 = AA.

How this is calculated

Formula

Aa × Aa → 1 AA : 2 Aa : 1 aa

Worked example, using the default values

  1. Identify Input Parameters
    Parent 1 Dominant Alleles = 1, Parent 2 Dominant Alleles = 1 = 2 input(s) provided
  2. Calculate AA Probability
    AA Probability
    25 = 25%
  3. Calculate Aa Probability
    Aa Probability
    50 = 50%
  4. Calculate aa Probability
    aa Probability
    25 = 25%
  5. Calculate Parent 1 Genotype
    Aa = Aa
  6. Calculate Parent 2 Genotype
    Aa = Aa

Engine last updated . Checked against 3 independently-derived tests how we verify calculators.

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