How this calculator works
Each parent contributes one of its two alleles with equal probability. Combining these gives four equally likely pairings. Upper-case A is treated as completely dominant for the phenotype summary; the genotype probabilities remain valid without that phenotype interpretation. Outcomes are probabilities for each offspring, not a guaranteed composition of a small family.
Formula
Each gamete pairing has probability 1/(2^loci × 2^loci). Genotype probability = matching pairings/total pairings. Independent-locus probabilities multiply.
Worked example
Aa crossed with Aa gives AA = 25%, Aa = 50% and aa = 25%. AA crossed with aa gives Aa = 100%.
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Frequently asked questions
Does dominant mean common?
No. Dominance describes the heterozygous phenotype; it does not determine population frequency.
Are the two parents ordered?
Switching the parents leaves genotype probabilities unchanged for this autosomal model.
Can this model sex-linked or incomplete dominance?
It reports one autosomal two-allele locus. Those inheritance patterns need different phenotype rules or chromosome modelling.