Heterochromia is a difference in color in the iris, either between the two eyes or within one eye. It comes in three kinds, complete, sectoral and central, and the central kind is common in hazel and green eyes. Our free eye color checker reads the inner and outer parts of each iris from a selfie.
What heterochromia means
The word comes from the Greek for different color. Doctors use it for any visible difference in iris color, and there are three main kinds.
- Complete heterochromia. Each eye is a clearly different color, for example one blue eye and one brown eye.
- Sectoral heterochromia. Part of one iris, often a wedge or patch, is a different color from the rest of it. It is also called partial heterochromia.
- Central heterochromia. The inner ring of the iris, around the pupil, is a different color from the outer part. It usually shows in both eyes, often as a gold or brown ring inside green, blue or gray.
How common is heterochromia
There is no reliable count, because mild heterochromia often goes unnoticed and nobody records it. What is clear is that the three kinds are not equally common.
- Complete heterochromia is rare in people, though it is common in some cats, dogs and horses.
- Sectoral heterochromia is uncommon, but a small patch is easy to miss without looking closely in good light.
- Central heterochromia is common. Many people with hazel or green eyes have it without knowing the name for it.
So if your eyes have a golden ring around the pupil, you are far from alone. Our guide to central heterochromia covers that pattern in detail, and our guide to the rarest eye colors puts it next to the colors themselves.
Why heterochromia happens
Eye color comes from melanin, the brown pigment in the front layer of the iris, and from how that layer scatters light. Heterochromia means the amount or spread of melanin differs from one eye to the other, or from one part of an iris to another.
- More melanin in a patch or a whole eye makes it look browner.
- Less melanin makes it look lighter, toward hazel, green, blue or gray.
Most heterochromia is present from birth or appears in early childhood as eye color settles. It can run in families, and in most people it is harmless and does not affect sight. Iris color is shaped by many genes, which our guide to eye color genetics explains in plain words.
Heterochromia can also appear later in life. When it does, an eye doctor should take a look to find out why. A new change in eye color, in one eye or both, is always worth showing to an eye doctor.
Heterochromia or just the light
Photos fool people about heterochromia all the time. Two matching eyes can look different in a picture for simple reasons.
- Light from one side. A window on one side of your face and a lamp on the other give each eye a different color of light.
- Shadow. One eye in shade looks darker and grayer than the other.
- Reflections. A bright reflection over one iris washes out its color.
- Pupil size. If one pupil is larger in the photo, that eye shows less iris and can look darker.
The simplest check is to look in a mirror facing a window in daylight, with no lamps on. If both eyes look the same there, the difference in your photo came from the light.
Our eye color checker reads each eye separately. When the two eyes read differently, it says so, and points out that uneven light is the most common reason.
Heterochromia in the eye color checker
Our checker looks for two of the three kinds.
- Two eyes that differ. Each eye gets its own reading. If they land on clearly different colors, the result notes it and suggests a photo in even light to compare.
- Central patterns. The checker splits each iris into an inner zone near the pupil and an outer zone near the edge. When the two zones are clearly different colors, the result names the pattern.
It does not look for small sectoral patches, because a wedge of color is easy to confuse with a reflection or a shadow from the lashes. It names a shade and nothing else. It cannot tell anything about eye health, and it is not a medical test.
How to photograph heterochromia
If you want a photo that shows your eye colors as they really are, the light matters more than the camera.
- Face a window in daylight, with no lamps or overhead lights on.
- Turn off the flash, which washes out iris color and can tint the pupils red.
- Hold the phone at eye level, about a forearm away, and look straight into the lens.
- Tap your eye on the screen to focus, and take a few shots.
- Avoid filters and beauty modes, which shift color.
The same steps give the most accurate result from our checker.
Colors and makeup for two eye colors
With complete heterochromia, you can pick colors that suit both eyes or play up one of them.
- Neutral browns and plums flatter almost every eye color, so they suit both eyes at once.
- Copper and bronze make a blue or gray eye stand out next to a brown one.
- Navy and teal make a brown eye look richer next to a lighter one.
For colors that suit your skin and hair as well as your eyes, try our seasonal color analysis.
Common myths about heterochromia
Two colored eyes attract a lot of folklore. A few claims come up again and again.
- It always means something is wrong. Most people with heterochromia are born with it, and in most of them it is harmless. It is a difference in pigment, like a freckle in the iris.
- One eye sees differently. Iris color does not change how sharp your sight is. Two different colored eyes usually see just as well as two matching ones.
- It is the same as having two eye colors in a photo. Uneven light can make matching eyes look different, as covered above. Real heterochromia shows in even daylight too.
- It only comes in blue and brown. Any two colors can pair up, including green and brown, gray and hazel, or blue and green.
Heterochromia in animals
Heterochromia is far more common in some animals than in people. White and bicolor cats, some dog breeds such as huskies and Australian shepherds, and some horses often have one blue eye and one brown or amber eye. In these animals it is usually linked to the genes that control white coat patches, which also reduce pigment in one iris. It is a good reminder that eye color comes down to how much pigment ends up where, in people as well as pets.
What we found in our own test photos
We ran our eye color checker on 701 public portraits of people whose eye color is recorded as a single color, so none of them were known to have heterochromia. Even so, the checker read the two eyes as clearly different colors in 3 percent of them. When we looked at those photos, the cause was easy to spot in most of them, one eye in shadow, hair, glasses or a reflection across one iris, colored light on one side, or a blurry photo. In a few, the two eyes looked the same to us, and the difference was too subtle to see.
That is the main lesson for anyone wondering about their own eyes from a photo. A single picture can make matching eyes look mismatched surprisingly often. Check in even daylight before deciding, and read how we ran the test on our methodology page.