Trihybrid Cross Calculator - Punnett Square

Trihybrid cross calculator allows you to create a Punnett square for 3 different traits easily.

CreatorFrank Zhao

Allele Reference Guide

Uppercase letters represent dominant alleles, while lowercase letters represent recessive alleles.

A,B,C

Dominant

Uppercase

a,b,c

Recessive

Lowercase

Mother's traits

Trait 1

More info

Trait 2

More info

Trait 3

More info

Father's traits

Trait 1

More info

Trait 2

More info

Trait 3

More info

AABBCC

AABBCc

AABBcc

AABbCC

AABbCc

AABbcc

AAbbCC

AAbbCc

AAbbcc

AaBBCC

AaBBCc

AaBBcc

AaBbCC

AaBbCc

AaBbcc

AabbCC

AabbCc

Aabbcc

aaBBCC

aaBBCc

aaBBcc

aaBbCC

aaBbCc

aaBbcc

aabbCC

aabbCc

aabbcc

♂️\♀️	ABC	ABc	AbC	Abc	aBC	aBc	abC	abc
ABC	AABBCC	AABBCc	AABbCC	AABbCc	AaBBCC	AaBBCc	AaBbCC	AaBbCc
ABc	AABBCc	AABBcc	AABbCc	AABbcc	AaBBCc	AaBBcc	AaBbCc	AaBbcc
AbC	AABbCC	AABbCc	AAbbCC	AAbbCc	AaBbCC	AaBbCc	AabbCC	AabbCc
Abc	AABbCc	AABbcc	AAbbCc	AAbbcc	AaBbCc	AaBbcc	AabbCc	Aabbcc
aBC	AaBBCC	AaBBCc	AaBbCC	AaBbCc	aaBBCC	aaBBCc	aaBbCC	aaBbCc
aBc	AaBBCc	AaBBcc	AaBbCc	AaBbcc	aaBBCc	aaBBcc	aaBbCc	aaBbcc
abC	AaBbCC	AaBbCc	AabbCC	AabbCc	aaBbCC	aaBbCc	aabbCC	aabbCc
abc	AaBbCc	AaBbcc	AabbCc	Aabbcc	aaBbCc	aaBbcc	aabbCc	aabbcc

Result	Genotype	Phenotype
AABBCC	AABBCC	ABC
AABBCc	AABBCc	ABC
AABBcc	AABBcc	ABc
AABbCC	AABbCC	ABC
AABbCc	AABbCc	ABC
AABbcc	AABbcc	ABc
AAbbCC	AAbbCC	AbC
AAbbCc	AAbbCc	AbC
AAbbcc	AAbbcc	Abc
AaBBCC	AaBBCC	ABC
AaBBCc	AaBBCc	ABC
AaBBcc	AaBBcc	ABc
AaBbCC	AaBbCC	ABC
AaBbCc	AaBbCc	ABC
AaBbcc	AaBbcc	ABc
AabbCC	AabbCC	AbC
AabbCc	AabbCc	AbC
Aabbcc	Aabbcc	Abc
aaBBCC	aaBBCC	aBC
aaBBCc	aaBBCc	aBC
aaBBcc	aaBBcc	aBc
aaBbCC	aaBbCC	aBC
aaBbCc	aaBbCc	aBC
aaBbcc	aaBbcc	aBc
aabbCC	aabbCC	abC
aabbCc	aabbCc	abC
aabbcc	aabbcc	abc

1Punnett square cell

G_{ij} = \operatorname{sort}(M_i + F_j)

2Offspring genotype frequency

P(g) = \frac{n_g}{64} \times 100\%

M_i

Mother gamete

F_j

Father gamete

G_{ij}

Offspring genotype

g

Genotype

n_g

Occurrences

64

Total outcomes

📚

Quick Navigation

This guide helps you use the trihybrid cross calculator confidently. You’ll learn what a trihybrid Punnett square represents, how to enter parent genotypes, how to sanity-check results, and how to interpret the genotype and phenotype breakdowns.

→Introduction / Overview
→What is a trihybrid Punnett square?
→How to use the trihybrid cross calculator
→How to do a trihybrid cross Punnett square
→Real-world examples
→Tips & best practices
→Calculation method
→Genetics basics
→FAQs
→Limitations

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Want smaller grids? Try the classic Punnett square calculator (1 trait) or the dihybrid cross calculator (2 traits).

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Introduction / Overview

This calculator builds a trihybrid Punnett square for three genes (A, B, and C). You select each parent’s genotype for every gene, and the tool generates:

an 8×8 Punnett grid (64 outcomes)
genotype frequencies (percentage for each of the 27 possible combined genotypes)
a genotype → phenotype mapping (dominant allele present vs recessive)

Who is this for? Students, educators, and anyone who wants a quick, visual way to verify a Mendelian 3-gene cross without manually writing 64 cells.

Reliability note: the calculator enumerates all gametes for both parents and combines them systematically, so the percentages are derived directly from the same 64-cell grid you see.

🧬

What is a trihybrid Punnett square?

A Punnett square is a structured way to list possible offspring genotypes from two parents. For one gene (one trait), it’s usually a small grid. For three genes, the grid grows quickly because each parent can form more unique gametes.

✅ In a trihybrid setup, each parent contributes one allele per gene. If the parent is heterozygous for all three genes (like AaBbCc), they can make 8 different gametes.

The complete Punnett square is formed by combining the 8 mother gametes with the 8 father gametes, giving a total of 64 genotype outcomes.

💡

Practical tip: If you only care about “dominant vs recessive” at the trait level, the phenotype table is often faster to read than the full 64-cell grid.

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How to use the trihybrid cross calculator

Quick start: pick the mother’s genotype for A, B, and C, then do the same for the father. As soon as both parents have valid genotypes, the calculator can generate the grid and frequencies.

Genotype options for each trait:

AA — homozygous dominant (both alleles dominant)
Aa — heterozygous (one dominant, one recessive)
aa — homozygous recessive (both alleles recessive)

Select the mother’s genotypes

Choose Trait 1 (A), Trait 2 (B), and Trait 3 (C).

Select the father’s genotypes

Repeat the same choices for the father.

Read the results

Open these sections for details: Offspring genotype frequency, Punnett square, and Phenotype and Genotype.

A tiny “by hand” check (optional)

Suppose you’re looking at one specific genotype that appears 2 times in the 64-cell grid. The calculator reports the percentage using:

P\,(\%)

=

\frac{n}{64}\times 100

=

\frac{2}{64}\times 100

=

3.125\%

This matches what you’ll see in Offspring genotype frequency.

🧾

How to do a trihybrid cross Punnett square

😱 A trihybrid Punnett square can be large: it uses an 8×8 grid (64 outcomes), 27 possible genotypes, and 8 possible gametes per parent.

If you’re curious about the mechanics, here’s the clean mental model (the calculator automates all of it):

Pick the parents’ genotypes

Choose the genotype for each trait (A, B, and C). For example: mother AaBbCc and father AaBbCc.

List each parent’s possible gametes

Each gamete contains one allele from each gene (A, B, C). A heterozygous genotype produces two allele options for that trait.

Combine gametes in an 8×8 grid

Put one parent’s 8 gametes across the top and the other parent’s 8 gametes down the side, then combine alleles inside each cell to form the offspring genotype.

How to calculate genotype probability

Build the Punnett square.
Count how many times a genotype appears (e.g., 2).
Divide by the total number of outcomes (64).
Multiply by 100 to get a percentage.

Genotype probability = (count / 64) × 100

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Real-World Examples / Use Cases

Below are practical scenarios you can replicate in the calculator. These examples are also a good way to spot -check your intuition.

Example 1: “All dominant genotype”

Background: both parents are AaBbCc.

Question: probability of AABBCC.

P(AABBCC)

=

\left(\frac{1}{4}\right)^3

=

\frac{1}{64}

=

1.5625\%

How to use it: open Offspring genotype frequency and locate AABBCC.

Example 2: “Exactly heterozygous for all three genes”

Inputs: mother AaBbCc, father AaBbCc.

Target genotype: AaBbCc.

P(AaBbCc)

=

\left(\frac{1}{2}\right)^3

=

\frac{1}{8}

=

12.5\%

How to apply: if you’re modeling a breeding plan, this is often the “maintain variability” outcome.

Example 3: One gene fixed

Background: both parents are AA for gene A, but heterozygous for B and C.

Inputs: A=AA, B=Bb, C=Cc for both parents.

Result: every offspring has A as AA; the grid shrinks in “effective variety” even though it still has 64 cells.

Example 4: Recessive risk check

If both parents are heterozygous for a trait (e.g., Aa), there’s a chance of a recessive phenotype.

Use the Phenotype and Genotype section to see which genotypes map to recessive outcomes.

Example 5: Teach independence

In classroom settings, set both parents to AaBbCc and compare single-gene ratios inside the bigger result table.

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Common Scenarios / When to Use

Great for

homework checks for Mendelian genetics (3 genes)
fast probability estimates for a specific combined genotype
teaching how independent assortment scales from 1 → 2 → 3 genes

Might be a poor fit if your biology case includes linkage (genes inherited together), incomplete dominance, codominance, epistasis, or sex-linked traits.

✅

Tips & Best Practices

💡

Start small: If you’re unsure, verify one gene first using the 1-trait calculator, then scale up.

Common mistakes to avoid

treating phenotype ratios as genotype ratios (they are not the same)
forgetting that each cell is one of 64 equally weighted outcomes in the full grid
assuming independence when your real genes are linked (see limitations)

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Calculation Method / Formula Explanation

Conceptually, the calculator does two things: (1) enumerates all gametes for each parent, then (2) combines them into offspring genotypes.

Genotype frequency

P(g)=\frac{n_g}{64}\times 100\%

Where $n_g$ is the number of cells matching genotype $g$ .

Variables

$g$ : a combined genotype like AaBbCc
$n_g$ : number of times that genotype appears in the 64 outcomes

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Related Concepts / Background Info

Genotype vs phenotype

A genotype is the allele pair for each gene (like Aa). A phenotype is the expressed trait. In simple dominant/recessive models, having at least one dominant allele (A) produces the dominant phenotype.

Independent assortment

The calculator assumes the genes assort independently. That’s why probabilities for multi-gene genotypes can be multiplied across genes in classic textbook cases.

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FAQs

What is a trihybrid cross Punnett square?

It’s a Punnett square that tracks three genes at once. The full grid has 64 outcomes (8 gametes from one parent × 8 gametes from the other).

What is the trihybrid cross Punnett square used for?

It is used to estimate the probability of different combinations of 3 traits in offspring — for example, the chance of inheriting certain dominant/recessive variants across three genes.

How many boxes are there in the trihybrid cross Punnett square?

There are 64 boxes in the full trihybrid Punnett square (an 8×8 grid).

How do I calculate genotype probability?

Count how many times the genotype appears in the 64 cells, then compute $\frac{n}{64}\times 100\%$ .

Why doesn’t my real-world case match the calculator?

Real traits can involve gene linkage, incomplete dominance, multiple alleles, or environmental effects. This calculator models the classic Mendelian dominant/recessive autosomal setup.

Can I share my exact setup with someone else?

Yes. Use the share button and enable sharing with results; the link preserves your parent genotypes and the expanded/collapsed state of result sections.

⚠️

Limitations / Disclaimers

This tool is for educational use. It assumes Mendelian inheritance with independent assortment.

Does not model linkage, epistasis, incomplete dominance, codominance, or sex-linked inheritance.
Does not represent clinical, medical, or breeding advice.