Punnett Square Calculator

Calculate genetic traits with our free Punnett Square Generator. Create monohybrid and dihybrid crosses for biology class instantly.

Genetic Cross Configuration

Parent 1 Genotype

Mother alleles

Parent 2 Genotype

Father alleles

Mastering Genetics

The Punnett square is a visual representation of Mendelian inheritance. It allows biologists to predict the probability of an offspring having a particular genotype. Whether you are studying simple dominance, incomplete dominance, or dihybrid crosses, this tool simplifies the combination process.

Monohybrid

Single trait cross (e.g. Flower Color). Results in a 2x2 grid.

Dihybrid

Two trait cross (e.g. Color & Height). Results in a 4x4 grid.

Inheritance

Visualize dominant vs recessive allele transmission.

How this Punnett Square Calculator works

The Punnett Square Generator runs entirely in your browser using JavaScript. Unlike other tools that send your data to a server, we process everything locally on your device. This guarantees 100% privacy and blazing fast speed.

No server interaction – data never leaves your device
Instant results since there is no network latency
Works offline once the page is loaded
Free to use with no usage limits

How to Use

Enter Genotypes

Input mother and father alleles (e.g., Aa for one trait, AaBb for two).

Calculate

Generate the Punnett Square grid automatically.

Analyze

View genotype probabilities and ratios instantly.

Example Usage

Classic Mendelian monohybrid cross.

Input

Parent 1: Aa, Parent 2: Aa

Output

25% AA, 50% Aa, 25% aa

Frequently Asked Questions

What is a Punnett Square?

A diagram used to predict the genotypes of a particular cross or breeding experiment. It is named after Reginald C. Punnett.

How do I format the input?

Use letters to represent alleles. Capital for dominant (A), lowercase for recessive (a). For two traits, combine them (e.g., AaBb).

Does order matter?

Standard convention is to keep same-letter alleles together (e.g., Aa, not aA) and dominant alleles first. Our tool handles the sorting for you.

Related Tools

The Punnett Square Generator is maintained by CodeItBro. We aim to provide the best free developer tools on the web. If you have feedback or suggestions, please visit our contact page.

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