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Reptile Genetics Calculator
Select your species and parent morphs to see every possible offspring genotype with probabilities. Supports recessive, co-dominant, dominant, and incomplete dominant traits across 50 species.
✓ 50 species supported✓ Used by 2,800+ breeders✓ Accurate Mendelian genetics
Choose your species
Frequently asked questions
How the calculator works
Recessive traits
Two copies needed for visual expression (aa). One copy = het (Aa). Breeding two hets gives 25% visual, 50% het, 25% normal.
Co-dominant traits
One copy (Aa) = visual expression. Two copies (AA) = "super" form. Breeding two visuals gives 25% super, 50% visual, 25% normal.
Polygenic / line-bred
These traits can't be reduced to simple Mendelian ratios. The calculator flags them but excludes them from probability calculations.
This tool is for educational purposes. Real-world outcomes depend on actual parental genetics being correctly identified. Always verify morph identification with your breeder.
