How to use the calculator
Pick your eye color and your partner's from the two menus. The moment both are set, the bars fill in with the odds of your baby having brown, hazel, green, or blue eyes. No sign-up, no email — the math runs in your browser.
Want a sharper read? Open Add grandparents and enter the four grandparents' eye colors. You don't need all of them; even one blue-eyed grandparent tells the calculator something a parent's eyes alone can't.
How to read your results
The top line shows the single most likely color. The bars underneath show every outcome and its share, so you see the whole spread, not only the winner. A baby eye color calculator deals in odds, so a 60% brown result means brown is likely — not certain.
Read a low number as "unlikely," not "impossible." Eye color is polygenic, meaning several genes shape it together, so even a 1% outcome can happen. That's biology, not a bug in the tool.
| Parents | Brown | Hazel | Green | Blue |
|---|---|---|---|---|
| Brown + Brown | 61% | 18% | 12% | 9% |
| Brown + Green | 39% | 21% | 28% | 11% |
| Brown + Blue | 44% | 12% | 16% | 29% |
| Green + Green | 3% | 22% | 62% | 14% |
| Green + Blue | 2% | 16% | 46% | 36% |
| Blue + Blue | 2% | 2% | 4% | 92% |
The eye colors, explained
Human eyes come in a handful of shades, but only a few can be predicted from genetics. Here's the full set, and how each maps to the calculator's four inputs.
- Brown — the most common color worldwide, from high melanin. A calculator input.
- Blue — low melanin, common in people of European descent. A calculator input.
- Green — rarer, found in roughly 2% of people. A calculator input.
- Hazel — a brown-green mix that shifts with the light. A calculator input, treated as an approximation.
- Gray — essentially blue with even less melanin. Pick Blue for the closest estimate.
- Amber — a rare golden or copper tone, in the brown family. Pick Brown for the closest estimate.
- Heterochromia — two different-colored eyes, or two colors in one iris. It's a trait of its own, not a color you inherit predictably, so the calculator doesn't model it.
That's why the calculator offers four choices, not seven: those four are the ones a genetic model can put real odds on. Gray and amber fold into their nearest neighbor, and heterochromia isn't inherited in a way any tool can forecast.
Eye colour is not the only trait worth a guess before the birth. If you have both parents' heights to hand, the child height predictor does the same kind of arithmetic for how tall they are likely to end up.
Why grandparents sharpen the estimate
A parent's eye color hides half the story. Someone with brown eyes can quietly carry a blue or green gene and pass it on — you wouldn't know from looking at them. Grandparents are how that hidden gene shows up.
Say you have brown eyes but your father's are blue. That means you carry a blue gene, and your baby could inherit it. Feed that grandparent into the calculator and the blue and green odds climb to match reality.
The genetics behind the numbers
The calculator uses a two-gene model of eye color. It maps each person's eye color to the gene versions most likely behind it, then combines the parents the way inheritance works. Brown tends to win over green, and green over blue, which is why brown is the most common result worldwide.
Hazel is the tricky one. It sits between brown and green on the melanin scale and isn't a clean genetic category, so we treat it as an approximation rather than exact science. For the full breakdown — the probability chart by parent pair, and why two blue-eyed parents can still have a brown-eyed baby — read what color eyes will my baby have.