Child Height Calculator: Predict Adult Height
Use this child height calculator to estimate your child’s future adult height from the biological parents’ heights and the child’s sex. It returns a mid-parental estimate and a broad expected range, not a guaranteed final height.
Predict your child’s adult height
What is a child height calculator?
A child height calculator estimates a boy’s or girl’s possible adult height from the biological parents’ heights. It uses the mid-parental height method: the formula adjusts for the child’s sex, averages the parent heights, and reports a broad expected range around the estimate.
How to use the child height calculator
For a more consistent child height calculator estimate, use measured biological-parent heights. Shoes, rounded guesses, and mixing centimeters with inches can noticeably change the result.
- Choose Metric or Imperial units.
- Select the child’s sex used by the mid-parental formula.
- Enter the biological father’s and mother’s measured heights.
- Select Estimate adult height and review both the midpoint and target range.
How the child height calculator estimates adult height
The mid-parental method adjusts one parent’s height by 13 cm, then averages the two values. The target range extends 10.2 cm, or about 4 inches, on either side of the midpoint.
For a boy
(mother’s height + 13 cm + father’s height) ÷ 2
For a girl
(father’s height − 13 cm + mother’s height) ÷ 2
Target range
estimated height ± 10.2 cm (± 4 in)
Child height calculator example
In this child height calculator example, a boy with a 180 cm father and a 165 cm mother has a midpoint of (165 + 13 + 180) ÷ 2 = 179 cm. The broad expected range is approximately 169–189 cm. For a girl with the same parents, the midpoint is 166 cm and the range is approximately 156–176 cm.
How accurate is a child height calculator?
A child height calculator provides a rough mid-parental estimate, not a precise forecast. The range is intentionally wide because children with the same parent heights can finish at different adult heights.
Genetics matters, but nutrition, long-term illness, hormones, sleep, medicines, puberty timing and measurement error can also influence growth. The result should never be used to diagnose short stature or decide whether treatment is needed.
A clinician evaluates growth over time using repeated measurements, growth charts and, when appropriate, family history, examination, laboratory testing or bone-age assessment. A single online estimate cannot replace that process. Use the child height calculator as one family-based reference and compare it with properly recorded growth over time. A clinician can interpret growth rate and development when the child height calculator range does not match the observed pattern.
Child height calculator vs. growth charts
A child height calculator starts with parent heights and estimates a future adult-height midpoint. A growth chart tracks a child’s measured height and growth rate over time against an age- and sex-specific reference population. They answer different questions, and the growth chart is more useful for identifying an unusual growth pattern.
What can affect a child’s adult height?
Adult height is influenced by many genetic variants inherited from both sides of a family, not only by the two parent heights entered here. Siblings can inherit different combinations, so even children with the same parents may reach noticeably different heights.
Healthy growth also depends on adequate nutrition, sleep, general health and normal hormone function. Chronic digestive, kidney, heart or endocrine conditions can affect growth in some children, while the timing and duration of puberty can move the final result above or below a simple midpoint.
Measurement quality matters when using a child height calculator. Measure each parent without shoes, standing upright against a flat wall, and record the value rather than relying on an old rounded number. For children, growth rate over months and years is more informative than a single measurement.
Related body calculators
These tools answer different adult measurement and fitness questions.
Child height calculator FAQ
How does a child height calculator estimate future height?
Enter both biological parents’ heights and select the child’s sex used by the formula. The mid-parental method returns a midpoint and a broad range, not an exact final height.
Why does the formula use the child’s sex?
The traditional mid-parental formula applies a 13 cm adjustment before averaging the parents’ heights. It is a population-based convention and does not capture every child’s biology or identity.
Is the target range a guarantee?
No. The ±10.2 cm range communicates uncertainty, and a child may finish inside or outside it.
Does current age, height or weight change this result?
Not in this version. This calculator only uses parent heights and the formula’s sex adjustment. Clinical growth prediction may consider current growth data and other evidence.
When should I ask a clinician about growth?
Seek qualified medical advice if growth has slowed, measurements cross growth-chart percentiles, puberty appears unusually early or late, or you have any concern about a child’s health.
Sources and methodology
The formula and expected range follow clinical descriptions of mid-parental height. These sources explain how to interpret the estimate and the limits of predicting a child’s future adult height.