Baby Eye Colour Prediction Tool

What determines eye colour?

Eye colour is a physical trait determined by the pairing of genes from both parents. There are three known eye colour genes, but only two are well understood. These genes explain the inheritance of brown, green, and blue eye colours, but they don't fully explain why some children have grey, hazel, or varying shades of colour. Genes are the basic units of heredity and come in pairs. Each gene has two alleles, which determine the appearance of any characteristic. One allele is dominant, meaning it is expressed more strongly, while the other is recessive.

How do dominant and recessive alleles affect eye colour?

In terms of eye colour, the brown allele is always dominant over the green and blue alleles. The green allele is dominant over the blue allele, and the blue allele is recessive. This means that brown eyes are the most common, with over half of the world's population having them. Environmental factors and certain drugs may also modify eye colour, suggesting that it's not solely determined by genetics.

Newborn eye colour at birth

Caucasian babies are born with blue eyes, regardless of the eye colours of their parents. African, Asian and Hispanic babies are generally born with brown eyes because of having more of the pigment Melanin in their eyes and skin.

Can a baby's eye colour change?

A child’s true eye colour cannot be determined until around their second birthday. But for many babies, their eyes have become their permanent colour before then.