Multi-Locus Genetics Engine
Select exact parental allele pairs. The engine simulates 16,384 gamete crosses to calculate true probabilities.
Rabbit Color Calculator: Predict Your Bunny Litter’s Coat Genetics
If you mix blue paint and yellow paint, you get green. But if you breed a Black rabbit with a Chocolate rabbit, you don’t get a muddy brown mix—you might end up with a litter of Lilac, Blue, or completely Black kittens (bunnies).
Rabbit breeding is not like mixing paint; it is a complex game of genetic inheritance. Because domestic rabbits have been bred for centuries, they carry a hidden library of recessive genes. What a rabbit looks like on the outside (its phenotype) rarely tells the whole story of the genes it carries on the inside (its genotype).
Whether you are a professional breeder striving for a specific American Rabbit Breeders Association (ARBA) standard or an enthusiast studying lagomorph biology, our Rabbit Color Calculator does the heavy mathematical lifting. By inputting the colors of the Sire (father) and Dam (mother), this tool uses Punnett square logic to forecast the statistical probabilities of their offspring’s coats.
The Genetic Alphabet: How Bunny Coat Colors Work
To understand the output of the calculator, you need a basic crash course in the “ABC’s” of rabbit genetics. A rabbit’s color is determined by five primary gene loci (locations on a chromosome), each with a dominant and recessive option.
- The A Locus (Agouti): Determines the pattern. A dominant ‘A’ means the rabbit has banded hair (like a wild rabbit or Chestnut). A recessive ‘a’ means the rabbit is a solid, “self” color (like solid Black).
- The B Locus (Black/Brown): Determines the base pigment. A dominant ‘B’ creates black pigment. A recessive ‘b’ creates chocolate (brown) pigment.
- The C Locus (Color): Determines if the color is expressed at all. A dominant ‘C’ allows full color. A recessive ‘c’ (the albino gene) wipes out all pigment, creating a Ruby-Eyed White (REW) rabbit, regardless of what other color genes they carry.
- The D Locus (Dense/Dilute): Determines color density. A dominant ‘D’ keeps the color rich (Black or Chocolate). A recessive ‘d’ dilutes the pigment (turning Black into Blue, and Chocolate into Lilac).
- The E Locus (Extension): Determines how far dark pigment extends down the hair shaft, controlling colors like Tortoiseshell or Harlequin.
Real-World Breeding: The “Surprise” Blue Litter
Let’s look at a common genetic surprise that baffles novice breeders.
Let’s look at a common genetic surprise that baffles novice breeders.
A breeder pairs a solid Black Sire with a solid Black Dam. They expect a litter of entirely Black kits. However, when the babies’ fur comes in, two of the kits are a stunning, powdery Blue.
How did two Black rabbits produce Blue babies?
The Rabbit Color Calculator reveals the hidden math. Both the Sire and the Dam had the visual dominant ‘D’ (Dense) gene, which made them black. However, both parents secretly carried the hidden recessive ‘d’ (dilute) gene passed down from their ancestors. When those two recessive ‘d’ genes met in the offspring, it “diluted” the black pigment, creating Blue. The calculator predicts this exact probability, helping breeders anticipate hidden recessives.
Instructions for the Rabbit Color Predictor
You don’t need a degree in genetics to use this tool. We have simplified the interface to give you instant probability charts.
- Input the Sire’s Color: Select the exact visual color (phenotype) of the father. If you know he carries specific hidden recessives (like carrying chocolate), select those advanced options if available.
- Input the Dam’s Color: Select the visual color of the mother.
- Analyze the Litter Odds: The calculator will instantly run the genetic combinations and provide a percentage breakdown. For example, it might output: 50% Black, 25% Blue, 25% Chocolate.
Dominant vs. Recessive Traits: A Quick Reference Guide
When planning your breeding program, use this cheat sheet to understand which colors will always overpower others if present.
| Gene Category | Dominant Trait (Overpowers) | Recessive Trait (Hidden) | Result of 2 Recessive Genes |
|---|---|---|---|
| Pattern (A) | Agouti (Banded hair) | Self (Solid hair) | Solid Colored Rabbit |
| Pigment (B) | Black Base | Chocolate Base | Chocolate Rabbit |
| Density (D) | Dense (Dark) | Dilute (Faded/Washed) | Blue or Lilac Rabbit |
| Expression (C) | Full Color | Albinism | Ruby-Eyed White (REW) |
Why Professional Breeders Rely on Genetic Forecasting
For ARBA-registered breeders, color calculation is not just a fun parlor trick; it is the foundation of their program.
Show rabbits are judged against a strict Standard of Perfection. If a breeder is trying to perfect the “Lilac” color line, they cannot blindly breed and hope for the best. Lilac requires a highly specific double-recessive combination (bbdd – chocolate base + dilute density).
By using the Rabbit Color Calculator, breeders can intentionally pair a Chocolate carrier with a Blue carrier to statistically produce the perfect Lilac, saving years of trial and error in their breeding lines. Once your carefully planned litter arrives, be sure to use our Rabbit Age Calculator to track their developmental milestones from tiny kits to healthy adults.
The Hidden Dangers of Double Dominant Genes
While color genetics are generally harmless, responsible breeding requires understanding how certain coat patterns are linked to fatal health conditions.
The most prominent example is the “En” gene, which creates the beautiful broken pattern (spots) seen in English Spots and Checkered Giants.
- If a rabbit inherits one ‘En’ gene, they have lovely spots.
- If a breeder intentionally pairs two spotted rabbits together, 25% of the babies will inherit two dominant ‘En’ genes (EnEn).
These kits are known as “Charlies.” They are often born completely white with very few spots, and tragically, many suffer from Megacolon, a fatal digestive defect. Genetic calculators help breeders avoid these lethal pairings.
Answers to Common Bunny Color Genetics Queries
Yes! Ruby-Eyed White (REW) is an “eraser” gene. A REW rabbit might genetically be a Black Agouti, but the albino gene erased the color. If you breed two REWs, and only one passes the albino gene, the babies will suddenly display the hidden colors of the parents.
“Tort” is short for Tortoiseshell. It is created by a specific mutation on the Extension (E) locus, causing the rabbit to have a colored body with darker “points” (ears, nose, feet, and tail).
No, it provides statistical probabilities. If the calculator says you have a 25% chance of getting a Chocolate kit, you could get an entire litter of Chocolates, or none at all. It is like flipping a coin.
Neither. Both the Sire and Dam contribute exactly 50% of the genetic code (one allele from each locus) to the offspring. Dominance is determined by the specific genes themselves, not by which parent they came from.
Trusted Lagomorph Genetic Resources
To dive deeper into the fascinating world of rabbit coat genetics, standard of perfection, and responsible breeding ethics, please visit these authoritative organizations:
- American Rabbit Breeders Association (ARBA): Official Website and Standards
- British Rabbit Council (BRC): Breed Standards and Information
- House Rabbit Society: Rabbit Welfare and Care Guidelines
Breeding Assessment Notice
This Rabbit Color Calculator provides mathematical probabilities based on standard Mendelian genetics for domestic rabbits. It cannot account for unexpressed (hidden) recessive traits unknown to the user, nor can it account for spontaneous genetic mutations. It is an educational tool and should be used alongside responsible, ethical breeding practices prioritizing animal health and welfare above coat aesthetics.