Horse Coat Color Calculator
Use known parent genotypes to estimate likely foal coat colors. This calculator models four major loci: Extension (E/e), Agouti (A/a), Cream (Cr), and Gray (G).
Sire (Stallion)
Dam (Mare)
Note: This is an educational horse coat color genetics calculator and does not include all modifiers (dun, silver, champagne, roan, tobiano, leopard complex, sooty, flaxen, etc.).
How This Horse Color Calculator Works
This tool applies basic Mendelian inheritance and Punnett-square logic across four important coat color genes. It combines parent genotype probabilities at each locus, then maps the resulting foal genotypes to visible color outcomes.
In plain terms: each parent contributes one allele per gene, and the calculator estimates all combinations and their percentage chances.
Genes Included in This Model
- Extension (E/e): Controls whether black pigment can be produced.
e/eproduces red-based coats (chestnut/sorrel). - Agouti (A/a): Restricts black pigment to points, producing bay when black pigment exists.
- Cream (Cr): Dilution gene. One copy creates single dilutes (palomino, buckskin, smoky black), two copies create double dilutes (cremello, perlino, smoky cream).
- Gray (G/g): Progressive depigmentation. Any foal with at least one
Gwill gray over time regardless of base coat.
Interpreting Results
Your output includes a ranked table of likely foal colors with probabilities. Gray outcomes are listed as overlays (for example, Gray over Bay) because gray masks the base coat as the horse ages.
Remember that a foal may be born with one shade and visually change over months or years, especially in gray horses.
Example Reading
If your result shows:
- 25% Buckskin
- 25% Gray over Buckskin
- 25% Bay
- 25% Gray over Bay
That means dilution and gray are both segregating in the mating, and all four outcomes are equally likely in this simplified model.
Why Breeders Use a Horse Coat Color Predictor
A horse coat color predictor helps with planning, record keeping, and informed expectations. It can be useful for:
- Breeding program planning across multiple seasons
- Understanding hidden recessive alleles
- Communicating expected outcomes with clients
- Comparing likely outcomes from different stallion pairings
Important Limitations
Real-world color genetics can be more complex than this model. Many phenotypes are modified by additional loci and by interactions not shown here. Use this as a high-quality first-pass estimate, then confirm assumptions with DNA testing when precision matters.
Best Practices for More Accurate Color Predictions
- Use lab-confirmed genotypes for both sire and dam.
- Track offspring outcomes to refine your herd records.
- Include additional test panels when breeding for specific colors or patterns.
- Treat phenotype (what you see) and genotype (what they carry) as separate data points.
Final Thoughts
This horse color calculator gives a practical, genetics-based estimate for common base and dilution outcomes. For casual use, it is a fast way to explore possibilities. For serious breeding decisions, pair it with modern equine DNA testing and pedigree-level data.