Baby eye color calculator
Choose each parent's eye color to see the rough chance of a brown-, green- or blue-eyed baby. It uses a simple two-gene teaching model. Real eye color depends on many genes, so treat the result as a guide, not a prediction.
Add grandparents (optional)
Rough chance for the baby
That family can't happen in this simple model, which shows how much it leaves out. The result ignores the grandparents.
A simple teaching model, not a prediction. Real eye color depends on many genes.
Chances for every parent combination
| Parents | Brown | Green or hazel | Blue or grey |
|---|---|---|---|
| Brown × Brown | 89% | 8% | 3% |
| Brown × Green or hazel | 67% | 28% | 6% |
| Brown × Blue or grey | 67% | 17% | 17% |
| Green or hazel × Green or hazel | <1% | 89% | 11% |
| Green or hazel × Blue or grey | <1% | 67% | 33% |
| Blue or grey × Blue or grey | <1% | <1% | >99% |
How to use it
- Pick each parent's eye color. Hazel counts as green, grey as blue.
- If you know them, open the grandparents section and add their eye colors too. They can change the result a lot.
- Read the bars as rough chances, not a forecast for your baby.
How eye color is inherited
Eye color comes mostly from how much melanin sits in the front layer of the iris. A lot of melanin looks brown. Very little looks blue, because of the way light scatters in the iris, and amounts in between look green or hazel. The biggest single influence is a region of chromosome 15 with two genes, OCA2 and HERC2, but at least eight other genes play smaller parts.
This calculator uses an older, simplified model with two genes: one where brown masks the other colors, and one where green masks blue. It treats each version of a gene as equally common, because real frequencies differ a lot from country to country. That makes it good for seeing how a hidden color can pass down and why grandparents matter, but not for predicting one particular child.
Why it's only a rough guide
- Eye color depends on many genes, not two, so real families often surprise this model.
- Two blue-eyed parents can have a brown-eyed child. It is uncommon, but it happens.
- Many babies are born with lighter eyes that darken over the first year or more.
- Hazel, grey and mixed colors don't fit neatly into three groups.
- Where brown eyes are the norm, as in much of the world, brown is even more likely than shown here.
- A surprising eye color says nothing about who a child's parents are.
When does a baby's eye color settle?
A baby's eyes can change color because melanin in the iris keeps building up after birth. In a study of healthy newborns at Stanford, 63% had brown eyes at birth, about 21% blue and about 6% green or hazel; the rest were hard to tell. Eyes that start out blue or grey are the ones most likely to darken.
Most of the change happens in the first year or two. A large study of twins found that most people have their lasting eye color by about age six, while a minority, roughly 10 to 15% of the white participants, kept changing slightly through adolescence and adulthood.
Frequently asked questions
Can two blue-eyed parents have a brown-eyed baby?
Yes, though it is uncommon. The simple model says no, but eye color depends on many genes, and other variants can raise the amount of melanin in the iris. MedlinePlus Genetics, from the US National Library of Medicine, notes that blue-eyed parents can have brown-eyed children.
Can brown-eyed parents have a blue-eyed baby?
Yes. Each parent can carry a hidden blue version of a gene, and if both pass it on, the baby can have blue eyes. Adding blue-eyed grandparents in the calculator shows how much more likely that becomes.
Which parent decides eye color?
Neither on their own. A baby gets one copy of each gene from each parent, and the mix of many genes sets the final color. A dominant version from one parent can mask a recessive one carried by the other.
When do babies' eyes change color?
Mostly in the first year, as melanin builds up in the iris, and sometimes into the second or third year. Most children have their lasting color by about age six, though a minority still change slightly later.
Are green eyes rare?
Fairly. Brown is by far the most common eye color, and green and hazel are much less common. In the Stanford newborn study, about 6% of babies had green or hazel eyes at birth, compared with 63% brown.
How accurate is this calculator?
It is a teaching model, not a genetic test. It gets broad patterns right, such as a hidden color skipping a generation, but it uses two genes where reality uses many, so individual families often differ from its numbers.