What color hair will my baby have?
Most often a shade near the darker parent, because darker pigment tends to dominate — but hair color is polygenic, so a real predictor gives probabilities rather than a single color. In the UK Biobank cohort of about 343,000 people, 41.1% had light brown hair, 37.2% dark brown, 11.5% blonde, 4.6% red and 4.2% black.
Two pigments do all the work. Eumelanin makes black and brown; pheomelanin makes red and the warm tones inside blonde. How much of each your hair holds is set by dozens of genes pulling in both directions, which is why two parents with the same hair color can have children who do not match either of them.
How hair color is inherited
The school version — one gene, brown dominant, blonde recessive — is wrong, and it is the reason most hair color calculators disagree with each other. The largest study of the question mapped hair color across the UK Biobank cohort and found blonde hair associated with over 200 genetic variants, describing the result as a continuum running from black through dark and light brown to blonde.
A continuum behaves differently from a switch. Children land near the average of their parents, with real spread either side, and the further a color sits from the population average the more often children drift back toward the middle. That is why this calculator reports a distribution across five colors and why the shape of that distribution shifts when you add grandparents: a grandparent reveals variants a parent carries without showing.
Why this is not a Punnett square
A Punnett square is the right tool for one gene with two versions. Hair color is neither. Draw the square anyway and you get clean quarters — 25% this, 75% that — which look authoritative and are not measurable in any population.
The clearest evidence is red hair. On the simple recessive story, inheriting a red variant from each parent makes a redhead. In UK Biobank it does not: 93% of red-haired people carry two MC1R variants, yet those people make up only 15% of everyone carrying two. The majority of two-variant carriers have blonde hair (15%) or light brown hair (41%). MC1R also explains just 73% of the inherited variation in red hair, with other genes accounting for most of the rest.
Can two dark-haired parents have a blonde baby?
Yes — and the mechanism is ordinary. Both parents carry lightening variants they do not display, and a child who inherits enough of them from both sides lands further up the scale than either parent.
It is worth being precise about how far up. Two dark brown parents most often have a dark brown child, with roughly a one in five chance of light brown; a fully blonde adult from that pairing is uncommon. What is common is a blonde baby from brown-haired parents — and that baby usually does not stay blonde. The two questions get mixed together constantly, and they have different answers.
Will my baby have red hair?
Red is the rarest of the five at 4.6%, and the odds are never zero. Because carrying red variants is far commoner than having red hair, two brown-haired parents can both be carriers without a redhead anywhere in the family album. This is the real reason red appears to skip generations.
Two red-haired parents raise the odds sharply, but not to certainty, which is the single biggest difference between this calculator and the others. If the answer you get looks surprising, it is describing genetics, not your family.
When does a baby's hair color settle?
Later than most people expect, and the numbers are striking. Following 476 children, researchers found that of those who were blond in early childhood, 143 — 70.8% of them — had brown hair by the age of 6 to 13.
That study measured something else worth knowing. Predicting those children's hair color from their actual DNA, using the forensic HIrisPlex panel, reached an AUC of 0.64 for blond and 0.64 for brown — close to a coin flip — against 0.97 for red. Reading real genotypes is barely better than guessing for the brown-to-blonde range in a child. No page that reads two dropdown menus can do better, and this one does not pretend to. For the full timeline, see when a baby's eyes and hair reach their final color.
Baby hair color chart by parent combination
The most likely outcome for each of the 25 parent pairings, straight from the model this page runs. Every cell is a probability distribution underneath — open the calculator above for the full spread.
| Mother \ Father | Black | Dark brown | Light brown | Blonde | Red |
|---|---|---|---|---|---|
| Black | Black 69% | Dark 57% | Dark 67% | Dark 50% | Dark 60% |
| Dark brown | Dark 57% | Dark 66% | Dark 47% | Light 59% | Dark 45% |
| Light brown | Dark 67% | Dark 47% | Light 59% | Light 48% | Light 51% |
| Blonde | Dark 50% | Light 59% | Light 48% | Blonde 72% | Light 44% |
| Red | Dark 60% | Dark 45% | Light 51% | Light 44% | Red 61% |
What this calculator will not do
- It will not name a color. Every answer is a spread, because the biology is a spread.
- It will not tell you anything about parentage. A child lighter or redder than both parents is normal inheritance, and reading it any other way is simply wrong.
- It will not claim an accuracy figure for itself. The published accuracy of DNA-based prediction is on this page; ours would be a number with nothing behind it.
- It will not pretend to fit everyone equally. The frequencies behind it come from a cohort of white British ancestry, where red hair is commoner and black hair rarer than in Southern European populations.
Hair texture is a separate question with separate genes — curls and color are inherited independently, so a blonde child can have tight curls and a dark child can be pin-straight. For the inheritance itself, our guide to what color hair your baby will have covers the biology in plain language.