Norwegian Forest Cat — Color Genetics & EMS Calculator

The Norwegian Forest Cat presents an extensive EMS color range encompassing all B-locus alleles (black, chocolate, cinnamon and dilutes), the Inhibitor (I) locus silver and golden series, and all accepted tabby patterns except ticked, making feline genetics management for NFO programs a multi-locus challenge. The Amber mutation (e allele at the Extension locus) was first documented in NFO and is now FIFe-accepted, producing a unique amber/light-amber phenotype that converts eumelanin to a modified phaeomelanin-like pigment. EMS color calculator tools must account for the e/e genotype and its interaction with the Agouti and Inhibitor loci, as amber cats uniquely display residual tabby pattern in amber coat.

Norwegian Forest Cat colour genetics: frequently asked questions

Which recessive colours do Norwegian Forest Cat cats commonly carry?
Amber (e) is a recessive allele at the Extension (E) locus; heterozygous carriers (Ee) are phenotypically black/standard. Homozygous amber (e/e) converts black pigment to amber/rufous tones. Light Amber occurs in e/e cats with the Agouti gene (A/-), while solid Amber arises in e/e + a/a cats. Chocolate (b), cinnamon (bl), and dilution (d) are all present as recessives in NFO populations.
What colour restrictions apply to the Norwegian Forest Cat breed standard?
Ticked tabby (25) is NOT accepted in Norwegian Forest Cat under FIFe standard — this is a key distinction from SIB and ABY. Colourpoint (cs) is not recognized in NFO. Dominant White (W) is permitted. Amber (e) is breed-specific and represents a unique genetic feature of the NFO not found in most other FIFe breeds.
Which coat patterns are typical for the Norwegian Forest Cat?
Classic (22), mackerel (23), and spotted (24) are all accepted. Ticked (25) is explicitly excluded. Silver series (I/-) produces silver tabby and smoke variants. Amber × silver combinations produce 'Light Amber Silver' phenotypes with complex EMS notation. The golden series (i/i + A/-) produces the popular 'golden NFO' show coat.

Popular EMS Colors

NFO n 23Black Mackerel Tabby
NFO ns 22Black Silver Classic Tabby
NFO ny 23Black Golden Mackerel Tabby
NFO d 22Red Classic Tabby
NFO f 23Black Tortie Mackerel Tabby
NFO n 03Black Bicolour

Calculate Colors for Norwegian Forest Cat

Free online cat color genetics calculator. Select the breed and appearance of the sire and dam to predict kitten coat colors, patterns and probabilities based on feline color genetics.

Sire (Father)
Dam (Mother)

Enter the appearance of both parents to calculate color predictions.

Related pages and tools

Cattery Management SoftwareCat Color CalculatorKitten Name GeneratorCattery Name GeneratorPricingNorwegian Forest Cat Breed Weight Charts