What eye color will the baby have if both parents have blue eyes?
If both parents have blue eyes, the simple two-gene model behind our calculator gives the baby the rough chances below. It is a teaching model, not a prediction: real eye color depends on many genes.
Rough chance for the baby
A simple teaching model, not a prediction. Real eye color depends on many genes.
Why these chances
In this two-gene model, blue eyes need two hidden copies at both genes, so two blue-eyed parents can only pass on blue and the model always gives a blue-eyed baby. Real eye color is more complicated. Other genes can raise the amount of melanin in the iris, so blue-eyed parents occasionally have a green- or brown-eyed child. MedlinePlus Genetics also notes that blue-eyed parents can have brown-eyed children.
What the grandparents change
Grandparents don't change anything here in the simple model: two blue-eyed parents can only pass on blue copies of its two genes.
Add grandparents in the calculator
What the model leaves out
The model uses only two genes and treats every version of a gene as equally common. In reality eye color depends on many genes, how common each version is differs from country to country, and hazel, grey and mixed colors don't fit neatly into three groups. Use the numbers to see how a hidden color can pass down, not to predict your baby.
Other parent combinations
- Brown × Brown
- Brown × Green or hazel
- Brown × Blue or grey
- Green or hazel × Green or hazel
- Green or hazel × Blue or grey
- Blue or grey × Blue or grey
Frequently asked questions
What eye color will the baby have if both parents have blue eyes?
In the simple model, roughly <1% brown, <1% green or hazel and >99% blue. Real families vary, because eye color depends on many genes.
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.
When will we know the baby's eye color?
Usually within the first year or two. Many babies are born with lighter eyes that darken as melanin builds up in the iris, and most children have their lasting eye color by about age six.