Cat Color Genetics Calculator (Kitten Coat Probability)
A simple Mendelian estimator for common cat coat traits: orange gene (sex-linked), dilution, longhair, tabby vs solid, and white spotting.
Quick answer
What you’ll get
- Orange gene outcome split by male vs female kittens
- Probabilities for dilution, longhair, tabby/solid, and white spotting
- Optional “example phenotype combos” (multiplied for simplicity)
Genetics can be more complex (multiple genes, modifiers, unknown carriers). This is a practical estimator — not a guarantee.
Parents
Orange gene (sex-linked)
This is the biggest driver of “orange vs non-orange” outcomes, and it differs for male vs female kittens.
“Tortie/Calico” means she has one orange X.
Male cats have one X and one Y.
Other traits (simple genes)
Choose what you know. If you’re unsure, pick “Unknown” (the calculator uses a neutral assumption).
Dilution (D/d)
Dilute = dd (blue/cream/lilac/fawn tones).
Longhair (L/l)
Longhair = ll (recessive).
Tabby vs solid (A/a)
Tabby requires at least one A. Solid = aa.
White spotting (S/s)
White spotting = S_ (dominant). Amount varies in real life.
Important note
Cat coat genetics can involve multiple genes (and modifiers) beyond this calculator. If you need precise results, genetic testing is the only reliable way. This tool is for learning and estimation.
How this calculator works (formulas)
1) Orange gene (X-linked)
Female kittens receive one X from mom and one X from dad. Male kittens receive one X from mom and a Y from dad.
We build Punnett squares separately for male vs female offspring to compute: orange, non-orange, and for females tortie/calico (mixed X alleles).
2) Autosomal traits (simple dominant/recessive)
For dilution, longhair, tabby, and white spotting, we combine parental gamete allele probabilities: P(child genotype) = P(allele from mom) × P(allele from dad).
Then we map genotypes to phenotypes (e.g., dilute requires dd).
3) Combo examples
Example phenotype combos multiply trait probabilities (a simplification): P(combo) ≈ P(trait1) × P(trait2) × ...
FAQ
Why does orange work differently for male and female kittens?
The orange gene is carried on the X chromosome. Male kittens have one X, females have two. That changes how the gene is inherited and why tortie/calico patterns are mostly female.
What does “carrier” mean?
A carrier has one hidden recessive allele (like Dd or Ll). The cat may look non-dilute or shorthair, but can produce dilute or longhair kittens if the other parent also contributes the recessive allele.
Is this the same as a genetic test?
No. Many coat traits involve multiple genes and modifiers. This is a simplified estimator. Genetic testing is needed for certainty.