What color hair will they have?
Hair color isn't fixed at birth — it's a story. Most kids start lighter and darken through early childhood, with a second shift at puberty. Tell us how each parent looked as a kid AND now, and we'll map the likely trajectory.
Some kids hold onto their early color into adulthood. Often the case when it darkens slowly through age 6+.
Starts blonde, gradually shifts to light brown — most darkening between ages 1 and 7.
A bigger shift than expected — common in families where one or both parents went from blonde-to-brown.
Hair darkens with age because follicles produce more eumelanin during puberty — but the amount varies wildly between families. By comparing your childhood color to your current color, we measure your family's tendency to darken. A parent who went from white-blonde to dark brown signals a strong darkening tendency for their kids; a parent who's still blonde at 30 doesn't.
Hair color is polygenic — at least a dozen genes contribute, and we can't see any of them from a form. We're modeling the population pattern that fits your inputs.
Individual babies vary widely. The timeline above is the average outcome, not a guarantee — and the color you see at month 5 is a much weaker predictor than the color at age 5, since baby hair often darkens significantly through early childhood.
Their hair, eyes, and height visualized as a family tree of traits — grandparents, parents, baby. Only Will They can ship this.
Hair color is polygenic. We compute a darkening signal from the gap between each parent's childhood color and current color (a parent who went from white-blonde to dark brown is more likely to pass darkening alleles than one still blonde at 30).
Red hair is recessive at MC1R — both parents need to carry a red-favoring variant for the child to be red, but lots of non-red parents are silent carriers (true rate ~25%).
We render an age-trajectory rather than a single color because most kids' hair darkens 2–4 stops between birth and puberty.
- We don't have your actual genotype — this is a population-level model from your inputs.
- Auburn / red-tinted browns sit on a continuum that no online quiz captures perfectly.
- For mixed-heritage families, the simplifying single-population statistics underestimate variance.
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