CollarDog Coat Color Genetics Calculator
Wondering what colors a litter could be? Enter each parent's coat genes and predict the puppies' colors, from black and red to blue, liver, isabella, and merle, with a clear double-merle safety warning.
Enter the Parents' Genes
Pick what you know for each parent. If a dog has been DNA-tested, enter its genotype; otherwise choose the color you see and leave carriers as the default.
How Dog Coat Color Is Inherited
A dog's color comes from several genes working in order. This calculator uses the main ones:
- E (base pigment): two copies of the recessive form (e/e) make a red or yellow dog (like a yellow Lab), hiding black-based color.
- K (dominant black): a dominant-black dog is a solid black-based color; without it, the agouti pattern (sable, tan points, agouti) shows.
- Brown (B): black versus liver / brown (recessive).
- Dilution (D): black becomes blue and liver becomes isabella / lilac (recessive).
- Merle (M): adds a marbled pattern. Black merle is often called blue merle.
Double Merle Warning
Breeding two merle dogs can produce double-merle puppies (M/M), which are largely white and have a high risk of deafness and blindness. Merle-to-merle breeding is strongly discouraged. This calculator flags that risk in the results.
Enter each parent's genes
Use DNA-test results if you have them, or the visible colors.
Predict
The calculator crosses the parents gene by gene.
See the odds
Read the likely puppy colors and any double-merle warning.
Frequently Asked Questions
Answers to the most common questions about dog coat color genetics.
A double merle carries two copies of the merle gene (M/M). It usually has large white areas and a high risk of deafness and blindness: studies report deafness in roughly 56% of double-merle Australian Shepherds and about 85% of double-merle Collie-type dogs. This is why breeding two merle dogs together is strongly discouraged.
Yes, if both black parents secretly carry the recessive red gene (E/e). Two carriers have about a 25% chance per puppy of producing a red or yellow puppy (e/e). If neither parent carries red, all puppies stay black-based.
Several genes combine. The E gene decides whether a dog can make black pigment or is recessive red/yellow. The K gene decides dominant black versus an agouti pattern. The brown gene sets black versus liver, the dilution gene turns black into blue and liver into isabella, and merle adds a marbled pattern. This tool covers the E, K, brown, dilution, and merle genes.
It shows the probabilities predicted by classic genetics for the main color genes, but it does not split every agouti pattern (sable, tan points, agouti) or include rarer genes, 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 canine coat color research. To go deeper, visit these trusted references: