Punnett Square Calculator
Calculate genetic cross outcomes for single traits
Punnett Square
| A | a | |
|---|---|---|
| A | AA | Aa(2) |
| a | Aa(2) | aa |
Genotype Results
AA
25% (1/4)
Aa
50% (2/4)
aa
25% (1/4)
How It Works
A Punnett square is a diagram used to predict the genotypes of a particular cross or breeding experiment. Each box represents a possible offspring genotype, determined by combining one allele from each parent.
Key Terms
- Homozygous Dominant (AA): Two dominant alleles
- Heterozygous (Aa): One dominant, one recessive
- Homozygous Recessive (aa): Two recessive alleles
- Phenotype: Physical appearance (dominant trait shows)
Understanding Punnett Squares
The Punnett square is a graphical method used to predict the genotypes of offspring from a genetic cross. Named after British geneticist Reginald Punnett, this tool helps visualize how alleles combine and what probability each genotype has of occurring.
Common Cross Examples
AA × AA
100% AA
All dominant
Aa × Aa
25% AA, 50% Aa, 25% aa
3:1 phenotype ratio
aa × AA
100% Aa
All heterozygous