Calcy Mate Logo
Biology Calculators

Punnett Square Calculator

Calculate offspring genotype probabilities (AA, Aa, aa) and visualize a 2x2 Punnett square for one-trait crosses.

Use this Punnett square calculator to predict genotype and phenotype probabilities from parental genotypes.

Choose mother and father genotypes (AA, Aa, aa), then combine parental alleles in a 2x2 Punnett square.

Genotype probabilities are found by counting AA, Aa, and aa outcomes and dividing by total outcomes.

Phenotype mapping for dominant/recessive mode is: AA -> A, Aa -> A, aa -> a.

Heterozygous means two different alleles (Aa), while homozygous means identical alleles (AA or aa).

Learning genetics? Enter parent genotypes to quickly predict offspring traits with our Punnett Square calculator!

A - Dominant allele
a - Recessive allele

Mother's genotype

Father's genotype

Chance for AA
%
Chance for Aa
%
Chance for aa
%

Punnett Square

♂\♀AA
AAAAA
aAaAa

Genotype to phenotype

GenotypePhenotype
AAA
AaA
aaa