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Eye Color Chart and Inheritance Calculator
Before you start: screens change how a color looks, so treat the swatches as a guide.
Eye color depends on the melanin in the front of the iris: a lot gives brown, a little gives green or hazel, almost none gives blue. Use the eye color chart to compare every natural color and the calculator to see the odds for a baby's eyes; it is a simplified model, not a prediction. A new color change in an adult needs an eye exam, for example with Doç. Dr. Muhammet Derda Özer (Doç. = Associate Professor).
Before you start: screens change how a color looks, so treat the swatches as a guide.
Eye colors chart: every natural eye color compared
Natural eye colors range from dark brown to pale blue, with amber, hazel, green and grey in between. All of them come from how much melanin sits in the front layers of the iris and how that layer scatters light.
| Eye color | What you see | How common |
|---|---|---|
| Brown | Light honey to near-black | More than half of people worldwide; 45% in the US |
| Amber | Mostly solid golden or copper | No reliable figure |
| Hazel | Shades of brown and green | About 5% worldwide; 18% in the US |
| Green | Pale to deep green | About 2% worldwide; 9% in the US |
| Blue | Pale to deep blue | 8–10% worldwide; 27% in the US |
| Grey | Silver to blue-grey | Rare, usually counted with blue |
Brown eye color
Brown eye color comes from the most melanin, and the more melanin, the darker the brown. It is the most common color worldwide.
Green eye color
Green eyes have no green pigment. They have little melanin, and the way light scatters in the iris adds the green tone. Only about 2% of people worldwide have them.
Hazel eye color and amber eye color
Hazel eyes show shades of brown and green. Amber eyes are a mostly solid golden or copper color, so amber and hazel are not the same.
Blue and grey eyes
Blue and grey eyes have the least melanin. Blue is structural: the iris fibres scatter short blue wavelengths back out, the same reason the sky looks blue.
What is the most rare eye color?
Green is usually named the rarest eye color, at about 2% of people worldwide. Grey and amber may be just as rare, but studies often group grey with blue and amber with brown or hazel, so there are no reliable figures for them.
How to read the eye color inheritance calculator
The calculator shows the approximate chance that a child has brown, green or blue eyes, based on both parents' colors. It uses a simplified model in which brown beats green and green beats blue.
| Parents | Brown | Green | Blue |
|---|---|---|---|
| Both brown | 75% | 18.8% | 6.3% |
| Brown and green | 50% | 37.5% | 12.5% |
| Brown and blue | 50% | 0% | 50% |
| Both green | 0% | 75% | 25% |
| Green and blue | 0% | 50% | 50% |
| Both blue | 0% | 1% | 99% |
Treat these as odds, not promises. Eye color is controlled by many genes, as many as 16 according to the American Academy of Ophthalmology, and a large 2021 study found more than 120 genetic associations. One region of chromosome 15, containing the genes OCA2 and HERC2, explains most of the difference between blue and brown. That is why a "0%" means very unlikely, not impossible: two blue-eyed parents can rarely have a brown-eyed child.
What about a newborn? Babies often have little iris pigment at birth, so blue eyes can darken as melanin builds up over about the first year. Wait until a baby is at least one before judging the final color.
Heterochromia eyes: central heterochromia and heterochromia iridis
Heterochromia is when a person's irises are different colors. The medical term is heterochromia iridis (often searched as "heterochromia iridum"). There are three forms:
- Complete heterochromia: one iris is a different color from the other.
- Partial (sectoral) heterochromia: part of one iris differs from the rest.
- Central heterochromia: an inner ring around the pupil is a different color from the outer iris.
Central heterochromia is a normal variant of iris pigment. Most children born with heterochromia have no other eye or health problems, but an infant with different-colored eyes should still be examined by an ophthalmologist.
Heterochromia that appears later in life is different. Causes include eye injury or bleeding, uveitis (inflammation inside the eye), glaucoma medicines and iris tumours. Prostaglandin glaucoma drops can permanently darken the iris.
When to see an eye doctor
See an ophthalmologist right away if the color of one or both of your eyes changes.
Get urgent help the same day if a color change comes with eye pain, sensitivity to light, a very red eye or blurred vision. These can be signs of uveitis (NHS). Go to emergency care if you cannot see.
Our surgeons assess these problems: Doç. Dr. Muhammet Derda Özer treats uveitis and eye tumours, and Prof. Dr. Ahmet Satıcı treats glaucoma.
This tool is for general information only. It is not a genetic test, cannot predict a child's eye color reliably and does not diagnose any eye condition. If you notice any change in the color of your eyes, or your baby's eyes look different from each other, see an eye doctor.
More free eye tools
Thinking about changing your eye color? Read eye colour change surgery: risks and why we don't offer it. Our surgeons treat eye disease; they do not perform cosmetic color change.
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Eye color chart and calculator: frequently asked questions
Nobody can say for certain. The calculator gives odds from the parents' colors, but eye color involves many genes, and a baby's color can change during the first year. Wait until your baby is at least one year old.
Rarely, yes. Two blue-eyed parents usually have blue-eyed children, but because several genes are involved, brown eyes are possible.
Yes. In the model the chance is about 6%, because brown-eyed parents can carry a hidden lighter copy of the gene.
Usually not when present from birth, and central heterochromia is a normal variant. A new difference in an adult needs an eye exam to rule out injury, inflammation or other disease.
Yes, but an obvious change is not normal. Causes include uveitis, pigment changes inside the eye, injury, iris tumours and some glaucoma drops, so see an ophthalmologist right away.
Sources for the facts on this page
- Brown color comes from melanin, more melanin = darker brown; less melanin scatters more light so the least-melanin eyes look blue; a little more melanin looks green or hazel; as many as 16 genes; babies' eyes may look blue at first and darken as melanin builds up within about 12 months; "half of all people in the U.S. have brown eyes", worldwide possibly more: American Academy of Ophthalmology, "Why Are Brown Eyes Most Common?" (7 Apr 2017; reviewed by Ivan R Schwab, MD) https://www.aao.org/eye-health/tips-prevention/why-are-brown-eyes-most-common
- 2014 Harris Poll in the US: 45% brown, 27% blue, 18% hazel, 9% green, 1% other; blue eyes get their color from scattered light; babies' irises often have little pigment and blue eyes can turn brown; genetics too complicated to predict a child's color from the parents: AAO, "Your Blue Eyes Aren't Really Blue" (16 Jun 2023; Ivan R Schwab, MD) https://www.aao.org/eye-health/tips-prevention/your-blue-eyes-arent-really-blue
- Brown is the most common color, more than half of people; green the rarest at about 2% of the world's population; green is not only a matter of melanin but of how light scatters: AAO, "Eye Color: Unique as a Fingerprint" https://www.aao.org/eye-health/tips-prevention/eye-color-unique-as-fingerprint
- Complete, partial and central heterochromia; congenital vs acquired causes (Horner's, Sturge-Weber, Waardenburg; trauma, bleeding, uveitis, glaucoma medications, iris tumours); children with heterochromia usually have no other problems; infants should be examined; adults with a change should be evaluated: AAO, "Heterochromia" https://www.aao.org/eye-health/diseases/what-is-heterochromia
- Central heterochromia is a normal variant of iris pigmentation: AAO, "Ask an Ophthalmologist: central heterochromia and iris rings" (Omar R Chaudhary, MD, 5 Feb 2015) https://www.aao.org/eye-health/ask-ophthalmologist-q/do-i-have-heterochromia
- Adult colour change: causes (Fuchs heterochromic iridocyclitis, pigment dispersion, uveitis, Horner's, trauma, iris freckles and nevi), prostaglandin glaucoma drops can cause permanent darkening, "see an ophthalmologist right away" for a distinct color change: AAO, "Why Are My Eyes Changing Color?" (2 May 2023; reviewed by Omar R Chaudhary, MD and Rebecca J Taylor, MD) https://www.aao.org/eye-health/tips-prevention/why-are-my-eyes-changing-color
- Heterochromia: most cases hereditary, caused by disease or injury; see a provider for a new change in one eye or differently colored eyes in an infant: MedlinePlus Medical Encyclopedia, "Heterochromia" (reviewed 1 Oct 2025) https://medlineplus.gov/ency/article/003319.htm
- Genes OCA2 and HERC2 on chromosome 15 play a major role; several other genes play smaller roles; blue-eyed parents can have brown-eyed children; eye color depends on melanin in the front of the iris: MedlinePlus Genetics, "Is eye color determined by genetics?" https://medlineplus.gov/genetics/understanding/traits/eyecolor/
- Blue is structural (collagen fibres scatter short blue wavelengths); grey, green and hazel shades depend on iris thickness and density and the pigment present; three-point blue / green-hazel / brown scale used in research; simple dominant-recessive model is "too simplistic"; 74% of the variance in eye colour explained by one interval on chromosome 15 (OCA2, HERC2 rs12913832); blue-eyed parents reported to have darker-eyed children: Sturm RA, Larsson M. "Genetics of human iris colour and patterns." Pigment Cell & Melanoma Research 2009;22:544–562. doi:10.1111/j.1755-148X.2009.00606.x
- Worldwide: 79% brown (2020 study), 8–10% blue, about 5% hazel, about 2% green; US: about 27% blue, 18% hazel, about 9% green; grey rare: Medical News Today, "Eye color percentages" (updated 24 Jun 2024; reviewed by Grace Zhang, MD) https://www.medicalnewstoday.com/articles/eye-color-percentage
- 70–80% of people worldwide have brown eyes, 2% green (the rarest); multiple genes act like dimmer switches; blue-eyed parents can carry hidden instructions for more melanin: The Tech Interactive, "Can Two Blue-Eyed Parents Have a Brown-Eyed Child?" (Elsa Tippy, 14 Apr 2026) https://www.thetech.org/ask-a-geneticist/articles/2026/blue-eyed-parents-brown-eyed-child/
- Amber is a mostly solid golden or copper color, not the same as hazel; one estimate of about 5%: All About Vision, "Amber Eyes" (John Egan, updated 15 Apr 2026) https://www.allaboutvision.com/eye-care/eye-anatomy/eye-color/amber/
- Brown includes honey and amber shades; green is the rarest naturally occurring color; grey is rare and grouped with blue in research, so prevalence is unclear; most people have stable eye color by age 6, but 10–15% of Caucasians can change through adolescence and adulthood: All About Vision, "How Eye Color Develops and Changes" (Burt Dubow, OD, FAAO; updated 16 Sep 2026) https://www.allaboutvision.com/eye-care/eye-anatomy/eye-color/overview-of-eye-colors/
- Published parent-to-child odds table (both brown 75/18.8/6.3; both blue 0/1/99; both green 0/75/25; brown + blue 50/0/50; brown + green 50/37.5/12.5; blue + green 0/50/50); over 120 genetic associations from a genome-wide study of about 193,000 people; predictors are "fun to play with" but ignore the complicated genetics: All About Vision, "Eye Color Genetics" (John Egan, updated 3 Sep 2026) https://www.allaboutvision.com/eye-care/eye-anatomy/eye-color/genetics/
- The 2021 genome-wide association study (up to 192,986 European participants, 124 independent associations, 61 genomic regions; Science Advances, 2021, doi:10.1126/sciadv.abd1239): reported by Sci.News https://www.sci.news/genetics/50-eye-color-genes-09451.html (the journal page blocked automated access; confirm against the paper)
- Babies' eye color: it takes about a year for melanocytes to finish; wait until at least 1 year before predicting the final color: Healthy Children (American Academy of Pediatrics), "Newborn Eye Color" (David Hill, MD, FAAP; updated 29 Jul 2021) https://www.healthychildren.org/English/ages-stages/baby/Pages/Newborn-Eye-Color.aspx
- Uveitis symptoms (eye pain, light sensitivity, red eyes, reduced or blurred vision) and urgency (urgent same-day advice for pain, light sensitivity, vision change, very red eyes; emergency if you cannot see): NHS, "Uveitis" https://www.nhs.uk/conditions/uveitis/
- Own calculations (not external facts): the odds table is reproduced by a simplified two-gene model in which brown is dominant over green and green over blue and each parent carries one hidden lighter copy: brown × brown gives 3/4 brown, 3/16 (18.75%) green, 1/16 (6.25%) blue; brown × green gives 1/2 brown, 3/8 (37.5%) green, 1/8 (12.5%) blue; green × green gives 3/4 green, 1/4 blue; brown × blue 1/2 brown, 1/2 blue; green × blue 1/2 green, 1/2 blue. The "blue × blue 99% / 1%" row is the published figure and is not produced by this model. Hazel ranges are the minimum and maximum of the brown and green cases.
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