Measure the parents
Use both biological parents’ heights, measured without shoes.
Height predictor
How tall will your child be?
Estimate adult height from both parents’ heights. A simple formula, a clear range, and context for the result.
Parents’ heights
Two measurements are all you need.
Your measurements stay in your browser.
Don’t know both parents’ heights? Check a height percentile
My Height Predictor
Boy formula. Mother: 160 cm. Father: 180 cm.
Mid-parental methodExample preview
Estimated adult height
176.5cm
5′ 9.5″
Family target range168–185 cm
An illustration for a boy with parents measuring 160 and 180 cm. Enter your family’s heights to see your estimate.
Example preview, not a personal result.
Published methods, explained
Measurements stay on your device
Free. No account needed.
How this height predictor works
Methods & sourcesCalculate the estimate
The mid-parental formula combines their heights into an adult height estimate.
Read the whole range
The range adds context. It isn’t a guarantee of how tall a child will grow.
The mid-parental height formula
This adult height calculator combines the biological parents’ heights with a sex-specific adjustment. All values below are in centimeters.
- Boys
- (mother + father + 13) ÷ 2
- Girls
- (mother + father − 13) ÷ 2
The family target range extends 8.5 cm below and above the estimate. It is a broad family reference, not a personal confidence interval.
Formula & range: Children’s MercyA worked example
Mother 160 cm, father 180 cm
For a boy176.5 cm
(160 + 180 + 13) ÷ 2
Family target range: 168–185 cm
For a girl163.5 cm
Try your family’s heights (160 + 180 − 13) ÷ 2
Family target range: 155–172 cm
Height prediction questions
What an adult height estimate can tell you, and where its limits are.
Read the methods & sourcesHow tall will my child be?
No calculator can know exactly. This tool uses the mid-parental formula to estimate an adult height from both biological parents’ heights. It gives a family-based starting point, not a personalized growth forecast.
How accurate is this height predictor?
The result includes a broad family target range of ±8.5 cm around the mid-parental estimate, following Children’s Mercy guidance. It is not a guaranteed outcome or an individually validated confidence interval. Puberty timing, nutrition, health and measurement error can all affect the result.
Why doesn’t this calculator ask for age or weight?
The mid-parental method only uses parents’ heights and the male or female formula. We only ask for information the calculation actually needs. A different model, Khamis–Roche, uses age, current height and weight too; it is not used by this calculator.
What if I don’t know a parent’s height?
This method needs both biological parents’ heights. We do not fill in an unknown height with a population average. If you know the child’s age and standing height, the height percentile calculator can describe their current position in the CDC reference instead.
How tall will I be if I’m already a teenager?
Parents’ heights offer a family-based estimate, but this formula does not use your age, current height or puberty timing. It cannot tell you how much growth you have left. You can compare your current height with the age-specific reference if you are under 20.
Can I use this for a baby or an adult?
Parents’ heights can offer a broad family estimate before a child grows, but this does not assess an infant’s growth. Infant measurements need an age-appropriate growth chart. For adults, this formula does not predict remaining growth or determine whether growth plates have closed.
Does a higher percentile mean healthier growth?
No. A percentile describes where a height sits in a reference population. The 50th percentile is the median, not a target or a health score. A pediatrician considers measurements over time and other information when assessing growth.