CollarCat Coat Color Genetics Calculator
Curious what colors a litter might be? Enter each parent's coat genes and predict the kittens' colors and patterns, including tortoiseshell and the famous X-linked orange gene.
Enter the Parents' Genes
Pick what you know for each parent. The brown, dilution, and tabby genes describe the cat's base (black-based) color. They are hidden under orange but are still passed on to the kittens, so if a parent is orange and you are unsure, just leave the defaults.
How Cat Coat Color Is Inherited
A cat's color comes from several genes working together. This calculator uses these genes:
- Orange (O) decides orange/red versus black-based color. It sits on the X chromosome, which is why tortoiseshell and calico cats are almost always female.
- Brown (B) sets black versus chocolate (black is dominant).
- Dilution (D) softens the color: black becomes blue (grey) and red becomes cream (recessive).
- Agouti (A) decides tabby versus solid (solid is recessive).
- Colorpoint (C) restricts color to the points (ears, face, paws, tail): the Siamese pattern, such as seal and blue point (recessive).
- White spotting adds white patches (bicolor, and calico when combined with tortie), while dominant white produces an all-white cat that masks every other color.
Why Tortoiseshells Are Female
A female has two X chromosomes, so she can carry orange on one and non-orange on the other, showing patches of both (a tortoiseshell). A male has a single X, so he is usually all one or the other. This tool reflects that sex link in its results.
Enter each parent's genes
Pick the colors you can see, and carriers if a DNA test is known.
Predict
The calculator crosses the parents gene by gene.
See the odds
Read the likely kitten colors, patterns, and their percentages.
Frequently Asked Questions
Answers to the most common questions about cat coat color genetics.
The orange gene sits on the X chromosome. Females have two X chromosomes, so a female can carry both orange and non-orange, showing patches of each (tortoiseshell). Males have only one X, so they are usually either all orange or all non-orange. A male tortoiseshell is very rare and results from a chromosome anomaly.
No. Orange is carried on the X chromosome, so at least one parent must carry the orange gene for a kitten to be orange. Two fully non-orange (black-based) parents cannot produce an orange kitten. A tortoiseshell mother, however, carries orange and can pass it on.
Several genes combine to make a cat's color. The orange gene decides orange versus black-based color, the brown gene sets black versus chocolate, the dilution gene turns black into blue (grey) and red into cream, and the agouti gene decides tabby versus solid. This tool also covers colorpoint and white spotting.
It shows the probabilities predicted by classic genetics for the main color genes (orange, brown, dilution, tabby, colorpoint, and white). Real kittens can still surprise you: it does not include every rare gene, and it cannot see hidden carrier genes. A DNA test from a lab such as UC Davis confirms the parents' true genotype.
Sources & Further Reading
The genetics on this page reflect published feline coat color research. To go deeper, visit these trusted references: