Child Height Predictor
Free child growth calculators on the CDC and WHO growth charts: height prediction, plus height, weight, BMI and head-circumference percentiles.
Predicted adult height
177 cm
5'10"
Likely range, low end
169 cm
5'6"
Likely range, high end
186 cm
6'1"
How the mid-parental method works
Average both parents' heights, then adjust 13cm for the child's sex: boys add 13cm, girls subtract it, because adult men average roughly 13cm taller than adult women. The result is the center of a wide range -- published as plus or minus 8.5cm -- inside which most, not all, children end up.
| Step | Worked example (mother 163cm, father 178cm) |
|---|---|
| Add both parents, plus 13cm for a boy | 163 + 178 + 13 = 354cm |
| Divide by two | 354 / 2 = 177.0cm |
| Apply the 8.5cm range | 168.5cm to 185.5cm |
For a girl with the same parents: (163 + 178 − 13) / 2 = 164.0cm.
Predict
Percentile calculators
Your child's height percentile and z-score from the CDC (2-20 years) or WHO (0-2 years) growth charts, with the P3-P97 row for their exact age.
Weight percentileYour child's weight percentile and z-score from the CDC (2-20 years) or WHO (0-2 years) growth charts, with the P3-P97 row for their exact age.
Baby percentile (0-24mo)Length, weight, head circumference and weight-for-length percentiles for babies 0-24 months, all from the WHO growth standards, in one form.
BMI percentileYour child's BMI-for-age percentile from the CDC growth charts (ages 2-20), with the CDC's own underweight/healthy/overweight/obesity category cutoffs.
Head circumferenceYour baby's head circumference percentile and z-score from the WHO growth standards (0-24 months), with the P3-P97 row for their exact age.
Full reference charts
Every calculator on this site is built on the same two published standards, shown in full as static reference tables and charts: the CDC 2000 growth charts (ages 2-20) and the WHO 2006 child growth standards (birth to 2 years).
Frequently Asked Questions
How accurate is a mid-parental height prediction?
It's a population-level rule of thumb, not a precise forecast for one child. Most children land within the 8.5cm (about 3.3 inch) range either side of the target, but genetics, nutrition, health during childhood, and puberty timing can all move the final number outside it. Treat it as a reasonable starting estimate, not a guarantee.
Where does the mid-parental formula come from?
It's the method described by J.M. Tanner and colleagues in the 1970 British longitudinal growth studies, and it's still the rule of thumb most pediatric references teach: average both parents' heights, then add or subtract 13cm depending on the child's sex, because adult men average about 13cm taller than adult women.
Why isn't there a Khamis-Roche calculator here?
Khamis-Roche (Khamis & Roche, 1994, Pediatrics) is a genuinely more accurate published method for ages 4-17 that also factors in the child's own current height, weight and age. But its coefficient table is age- and sex-specific and published only in the original paper -- we didn't find a way to reproduce it reliably from secondary sources, and guessing at a YMYL calculation's constants is worse than not shipping it. This site uses mid-parental height only, and says so here rather than quietly approximating it.
What if my child is already a teenager?
The height calculator adds a second method, percentile tracking, alongside mid-parental height, plus a table of predicted adult height by your teen's current height percentile.
Is this the same as my pediatrician's growth chart?
The percentile calculators on this site use the exact same CDC and WHO reference data pediatricians use. This height predictor is different: it estimates a future adult height from parents' heights, which a growth chart alone can't do for a young child.
These calculators estimate from published population reference data and published rules of thumb -- not a diagnosis, and not a substitute for your pediatrician, who tracks your child's own growth curve over time.