Punnett Square Calculator
Build monohybrid, dihybrid, and trihybrid Punnett squares plus ABO blood type and X-linked crosses, with reduced genotypic and phenotypic ratios, gametes, and every genetic convention named.
At a glance
- Computes
- Monohybrid to trihybrid squares, ABO and X-linked crosses, and reduced ratios.
- You supply
- Both parent genotypes, the cross type, and optional trait labels.
- Use when
- Independent loci with simple dominance, or the blood-type and X-linked cases named.
- Not for
- Allele frequencies across a whole population instead of a single cross. Hardy-Weinberg Calculator
Punnett square
Enter a cross
Monohybrid, dihybrid, trihybrid, ABO blood type, and X-linked crosses.
| Outcome | Count | Fraction | Percent |
|---|
| Outcome | Count | Fraction | Percent |
|---|
Show the grid
parent gametes are combined in a Cartesian grid
How?
How this is calculated
Each parent's genotype is read exactly as entered, so the probabilities follow from what you type and the heterozygous case is never inferred. The calculator lists every gamete each parent can make, combines each parent 1 gamete with each parent 2 gamete, counts the resulting genotypes, and reduces the counts to the genotypic and phenotypic ratio.
The case-dominance modes (monohybrid, dihybrid, trihybrid) read uppercase as dominant. ABO blood type uses a three-allele codominance model where I^A and I^B are codominant and both dominant over i. X-linked crosses treat the Y as carrying no allele, so males are hemizygous and phenotype is reported per sex.
Formula: parent gametes are combined in a Cartesian grid
Sources
- OpenStax Biology 2e, Characteristics and Traits. OpenStax. Retrieved .
- Biology LibreTexts, Multiple Alleles. LibreTexts. Retrieved .
- OpenStax Biology 2e, Laws of Inheritance. OpenStax. Retrieved .
Method last reviewed