Eggs

Egg Color Chart: Chicken Breeds by Shell Color, and Why Eggs Differ

Field guide · Updated October 16, 2026 · about 8 min read

Every chicken egg starts out with a white shell. The color comes from pigment the hen adds in the shell gland: brown protoporphyrin on the surface, blue biliverdin through the shell, or both. Which pigment, and how much, depends mostly on breed. The chart below collects what extension services and breed references list for each breed, including where they disagree.

Egg color chart by breed

Shades vary within every color group and between strains of the same breed. Where references describe a breed differently, both descriptions are shown.

Fort Bend = Texas A&M AgriLife Extension, Fort Bend County, Chicken Breeds and the Colors of Their Eggs. TLC = The Livestock Conservancy's Heritage Chicken Breed Comparison Chart. Oklahoma State = Breeds of Livestock pages. For eggs per year, size and temperament of common breeds, see the breed directory.

Why shell colors differ: two pigments

Shells are made of calcium carbonate and start out white; the color is added in the shell gland, the fourth of five stages of egg formation, a process that takes a little over 24 hours from start to finish (Texas A&M AgriLife). Researchers name three main eggshell pigments: protoporphyrin IX, biliverdin and biliverdin's zinc chelate (UF/IFAS; Wang et al. 2013).

• Brown: protoporphyrin IX. A 2015 review in Poultry Science (Samiullah, Roberts and Chousalkar) identifies it as the main pigment of brown shells, deposited through the shell layers but most heavily in the outer shell and the cuticle. UF/IFAS adds that most of the pigment sits in the cuticle, laid down in the final hours of shell formation, so the cuticle largely sets how dark a brown egg looks. Because the pigment goes on late, the inside of most brown shells stays white (Texas A&M AgriLife), and soaking a brown egg in vinegar dissolves the colored outer layer (Fort Bend).
• Blue: biliverdin. Blue eggs are colored mainly by biliverdin (Wang et al.), which Texas A&M AgriLife describes as coloring the shell inside and out.
• Green and olive: both. A blue shell with a brown coating on top reads as green; the darker the brown, the more olive the egg (Texas A&M AgriLife).
• White: a white egg is a shell with little or no added pigment.

The genetics of blue eggs

Blue shell color is inherited as an autosomal dominant trait, and hens carrying two copies lay darker blue eggs than hens with one (Wang et al. 2013, PLoS Genetics). Wang's team traced it to an insertion of an endogenous retrovirus, EAV-HP, next to a gene called SLCO1B3 on chromosome 1, which raises the gene's activity in the shell gland. The insertion sits at a slightly different spot in the Araucana than in two Chinese blue-egg breeds, the Dongxiang and Lushi, which the authors read as independent origins on different continents.

A second 2013 study (Wragg et al., PLoS ONE) found the same insertion, with 100% sequence identity, in the Mapuche fowl of Chile and in European blue-egg breeds, and concluded it arose after chickens were domesticated. Brown-shell genetics are less settled: the Poultry Science review notes that the control of pigment deposition in commercial brown layers is not fully understood.

Crossbred layers are where most green eggs come from. Oklahoma State stresses that Easter Eggers, which lay blue or green eggs, "don't conform to any breed characteristics." Crossing a blue-egg breed with a brown-egg breed gives the olive egger, and a darker brown parent gives a more olive egg (Texas A&M AgriLife).

Why a hen's eggs change shade

A hen's basic egg color is fixed by her genes, but the shade can drift. Texas A&M AgriLife says age "may produce an egg of a lighter or darker shade" without changing the basic color; UF/IFAS is more specific for brown eggs, saying pigment intensity declines as hens age.

Speckles are a separate matter: Texas A&M AgriLife describes them as extra calcium deposits, linked to disrupted calcification, a shell gland defect or excess calcium, and notes that speckled shells are technically abnormal though sometimes stronger. A sudden change across a flock, with other signs of illness, is a reason to call a veterinarian or your county extension office.

Earlobes as a clue

Earlobe color is a rule of thumb, not a guarantee. Fort Bend says it "usually" predicts egg color: white earlobes, white eggs; red earlobes, brown eggs. Texas A&M's Gregory Archer says "generally," and Kentucky's Jacquie Jacob frames it for commercial birds: white-feathered, white-earlobed hens lay white eggs, and red-feathered, red-earlobed hens lay brown. Oklahoma State's Barnevelder, with red earlobes and brown eggs, fits the pattern.

Does shell color matter in the kitchen?

• Not for grade or quality. USDA says shell color does not affect egg quality and is not a factor in the U.S. standards and grades for shell eggs.
• Not for taste. Brown and white eggs "basically taste the same and have the same functional properties" (Jacob); diet can change taste.
• Not for yolk color. That comes from the hen's diet (Texas A&M AgriLife).
• Sometimes for size and price. USDA notes brown eggs are bigger on average because of the breeds that lay them, and cost more to produce.

Planning a colorful egg basket: checklist

1. Pick breeds from the chart, then check them in the breed directory for laying rate, size and climate.
2. For blue eggs from a recognized breed, look at Ameraucana, Araucana or Cream Legbar; Easter Eggers lay blue or green eggs but follow no breed standard (Oklahoma State).
3. For chocolate brown, look at Marans or Welsummers; expect shades to vary by strain.
4. Expect brown eggs to lighten as hens age; see how long hens keep laying.
5. Keep stress low: crowding and fright can pale shells.
6. Whatever the color, collect and store eggs the same way; see egg handling and washing.