Horse Color Calculator
Enter the sire's and dam's coat color test results and get the odds of each foal color, from chestnut, bay and black to palomino, buckskin, cremello and grullo.
Enter each parent’s coat colour DNA test results. Defaults: a buckskin stallion carrying red and black, and a chestnut mare.
buckskin sire × chestnut dam
Equally most likely: chestnut, palomino (25% each)
- chestnut25%
- palomino25%
- bay18.8%
- buckskin18.8%
- black6.3%
- smoky black6.3%
Gene by gene
| Extension (red factor) | E/e 50% · e/e 50% |
| Agouti | A/a 50% · A/A 25% · a/a 25% |
| Cream | N/N 50% · N/Cr 50% |
| Dun | nd2/nd2 100% |
| Gray | N/N 100% |
What this page cannot tell you
The exact shade, or any white markings and patterns. Only five genes are modelled; tobiano, frame, sabino, leopard (appaloosa), roan, silver, champagne and pearl are not. Odds are per foal — each foal is a new draw — and they are only as good as the test results entered.
How to work out a foal's likely coat color
- Get both parents' test results. A coat color panel reports a genotype for each gene, such as E/e or N/Cr.
- Enter the sire's genotypes. Extension, Agouti, Cream, Dun and Gray.
- Enter the dam's genotypes. The hints say what each color usually means if a result is missing.
- Read the odds. Each possible foal color with its chance, plus the odds for each gene.
10 situations where foal color odds help
Choosing a stallion for a color
Compare the odds of a palomino or buckskin foal from two candidate stallions.
Avoiding surprise chestnuts
Two black-based parents that both carry e can still produce a chestnut — the odds show how often.
Breeding for cremello or perlino
Double cream needs a cream allele from each parent.
Pricing a breeding
Some breeders charge more for color-producing stallions; check what the color odds actually are.
Understanding a homozygous stallion
An E/E stallion cannot sire a chestnut, whatever the mare.
Explaining a foal's color
Work backwards: which genotypes could have produced it?
Planning a dun breeding program
See how often D passes on from a D/nd2 parent.
Checking gray inheritance
One gray parent with a single G gives a gray foal half the time.
Answering buyer questions
Give the real odds instead of 'should be colored'.
Learning how color genes stack
The gene-by-gene table shows how each result combines into a coat name.
Where the genetics come from
Each gene's alleles and their effects are taken from the UC Davis Veterinary Genetics Laboratory's test pages, read on the date shown on the result. Extension (red factor): E allows black pigment; horses that are e/e (or carry the rarer ea) produce no black pigment and are red-based, and red factor overrides agouti. Agouti: A restricts black pigment to the points (bay); a/a spreads it over the body (black). Cream is incompletely dominant: one copy gives palomino, buckskin or smoky black, two give cremello, perlino or smoky cream. Dun is dominant and dilutes both red and black pigment with primitive markings; nd1 and nd2 are the non-dun alleles. Gray is dominant and progressively whitens any base color, often to almost white by 6–12 years.
For each gene, the page crosses the two parents' genotypes the standard Mendelian way — each parent passes one of its two alleles, each with a 50% chance — and then combines the five genes, treating them as inherited independently. Each combination is named from the base color (chestnut, bay or black) and the dilutions. The VGL notes that 'the names assigned to the various dun shades vary by breed', so a bay with dun is shown as 'bay + dun' rather than a breed-specific name.
Results are percentages per foal. With small numbers of foals, real outcomes can differ a lot from the odds, the same way a coin can land heads three times running.
Limits: white-pattern and spotting genes (tobiano, frame overo, sabino, splash, leopard complex), roan, silver, champagne and pearl are not modelled, and nor are brown/seal shades. Results are only as accurate as the genotypes entered; a guess from a horse's appearance can be wrong, especially for carriers. For breeding decisions, test both parents through a laboratory.
Frequently asked questions
What color foal will two bay horses have?
It depends on what they carry. Two bays that are both E/e A/a give 56.25% bay, 18.75% black and 25% chestnut. Two E/E A/A bays give only bays.
Can two chestnuts have a black or bay foal?
No. Chestnuts are e/e and can only pass on e, so every foal is chestnut-based, unless a gray or other gene changes its look.
How do I get a palomino?
A chestnut base plus one cream allele. Palomino × chestnut gives 50% palomino; cremello × chestnut gives 100% palomino.
What does E/E mean?
The horse carries two black-pigment alleles and cannot have a chestnut foal, whatever the mate.
Why doesn't agouti matter on my chestnut?
Red factor overrides agouti: an e/e horse makes no black pigment, so agouti has nothing to act on. It is still passed to the foals.
Will my foal be gray?
If one parent is N/G, each foal has a 50% chance; if a parent is G/G, every foal will gray. Grays are born another color and lighten with age.
Does this cover pinto and appaloosa patterns?
No. Only Extension, Agouti, Cream, Dun and Gray are modelled.
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