How accurate is this?

About eight centimetres either way, so a sixteen centimetre range. It is a rough guide rather than a prediction, and a growth chart tracked over time is far more informative.

Can nutrition change adult height?

Substantially. Height is highly heritable within a well-nourished population, and undernutrition during growth reduces it regardless of genetics.

Health & Fitnesschildren

Child Height Predictor

Adult height predicted from parent heights. The mid-parental method carries about eight centimetres of error either way, which is a range of sixteen centimetres and much wider than the single number suggests.

Also called: adult height predictor, how tall will my child be.

Predicted adult height

174

174 cm by the mid-parental method, with a likely range of 166 to 182 cm. The error on this method is about 8 cm either way, which is wider than most people expect. The error is about eight centimetres either way. Serial measurements on a growth chart tell you far more than a prediction from parent heights.

Mid-parental height

167.5

Lower bound

166

Upper bound

182

Error margin

Growth remaining, if a current height is given

On the method

The error is about eight centimetres either way. Serial measurements on a growth chart tell you far more than a prediction from parent heights.

How this is calculated

For reference only. Verify against your clinical protocol before acting on this number.

Method and background

This is what the calculation gives for the numbers you entered. It is an estimate, not advice, and it knows nothing about your situation beyond those numbers. Rules for United States change on a published schedule; the effective date is shown on every rule-based tool.

How this is calculated

Average the parents' heights and add or subtract 6.5 centimetres depending on the child's sex. The method is simple and its error is large: roughly eight centimetres either side, so a prediction of 178 means somewhere between 170 and 186. Height is highly heritable but polygenic, and nutrition and health during growth move it substantially. Serial measurements plotted on a growth chart tell you far more than any prediction from parents.

the mid-parental method adds 13 cm for a boy and subtracts it for a girl

h_m, h_f: Parent heights

Worked examples

Each of these is asserted on every build. If a change to the engine ever moved one of these answers, the build would fail before the page could print it.

a boy with 160 and 175 cm parents

Mother height: 160 cm
Father height: 175 cm
Child: Boy
Current height, if known: 0 cm
Current age: 0

Predicted adult height174

167.5 plus 6.5; the band is 8 cm either way

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a girl with the same parents

Mother height: 160 cm
Father height: 175 cm
Child: Girl
Current height, if known: 0 cm
Current age: 0

Predicted adult height161

boundary: the 13 cm sex difference, split either side

Open this example

Method and limits

What it assumes

Both biological parents reached their genetic potential, which nutrition can prevent.

What it deliberately does not model

The error band is about eight centimetres either way, which is wider than the prediction is useful.
Nutrition, chronic illness and endocrine conditions all affect final height.
A child tracking consistently off their growth curve warrants medical review rather than a calculator.

Formula version 1.0.0 · definition 1.0.0 · United States · Report a problem with this calculator

Frequently asked questions

How accurate is this?: About eight centimetres either way, so a sixteen centimetre range. It is a rough guide rather than a prediction, and a growth chart tracked over time is far more informative.
Can nutrition change adult height?: Substantially. Height is highly heritable within a well-nourished population, and undernutrition during growth reduces it regardless of genetics.