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Foal coat color calculator

Pick the sire's and dam's colors, or enter their color test results, to see the odds of every foal color. The calculator follows ten genes, from the basic red and black to cream, dun, champagne, silver, gray, roan, tobiano and frame overo.

Enter your numbers
Sire
Fills in typical genes. Adjust any gene from a DNA test below.
Genes (from a color test)
Dam
Fills in typical genes. Adjust any gene from a DNA test below.
Genes (from a color test)

Most likely foal

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Hidden genes change the odds

A bay can carry red (e), a chestnut can hide agouti, and cream or silver can be invisible on some colors. The quick picks assume the most common hidden genes; a $25–50 color test gives exact answers.

How horse color genetics works

Every foal gets one copy of each gene from each parent, chosen at random. Coat color starts with two genes:

Extension: E (black pigment possible) or e (red only). Two e's = chestnut.
Agouti: A keeps black to the points (bay). Two a's with an E = black.

Then dilution genes lighten the base: one cream copy turns chestnut into palomino, bay into buckskin and black into smoky black; two copies make cremello, perlino or smoky cream. Dun adds a dorsal stripe and leg barring (bay dun, red dun, grulla). Champagne lightens coat and skin; silver lightens black pigment and hides on chestnuts.

Gray is dominant and turns any color white with age; a gray foal is born its base color. Roan, tobiano and frame overo add white patterns.

Lethal white overo

A foal with two copies of the frame overo gene (O/O) is born all white with a non-working gut and cannot survive. Two carriers bred together have a 25% chance of it. Because frame overo can be nearly invisible, test both horses before breeding any overo, solid Paint or colored Quarter Horse.

This calculator covers the ten most common color genes. Rarer ones (leopard complex, sabino, splash white, pearl, brindle) aren't included yet. Plan the due date with the foaling date calculator.

Frequently asked questions

Why does the calculator need color test results instead of just what color the parents look like?

Visible coat color doesn't always reveal every gene a horse carries — a horse can visibly be one color while carrying a hidden copy of another gene (like a hidden cream or silver allele), so an actual genetic test result gives more reliable odds than color alone.

Why can two chestnut parents never produce a black foal?

Black pigment requires at least one copy of the E allele at the Extension gene, and a chestnut horse is genetically ee — with no E allele in either parent to pass on, a black-pigmented foal (bay, black, or brown) is genetically impossible from that pairing.

Does this predict every possible foal color?

It covers ten of the major, well-established coat color and pattern genes, but there are additional, rarer modifiers in some breeds that aren't included — treat the result as strong odds on the main color outcomes, not an exhaustive guarantee.

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