Height Calculator
This free height calculator predicts a child's likely adult height using well-known methods such as the mid-parental (parents' average) formula. While genetics, nutrition, and health all influence final height, these estimates give parents a useful guide to how tall their child may grow. Enter the parents' heights — and optionally the child's current age and height — and the calculator estimates the future adult height.
How to Use the Height Calculator
- Enter the mother's height.
- Enter the father's height.
- Select the child's sex (and optionally current age and height).
- Calculate — see the predicted adult height.
The Mid-Parental Height Formula
A common child height predictor uses the parents' average:
Boys: ((Mother's height + Father's height) ÷ 2) + 6.5 cm
Girls: ((Mother's height + Father's height) ÷ 2) − 6.5 cm
For example, with a mother of 162 cm and a father of 178 cm, a boy's predicted height is (340 ÷ 2) + 6.5 = 176.5 cm, and a girl's is 163.5 cm. The actual height typically falls within about 8.5 cm of this estimate.
What Influences a Child's Height
| Factor | Role |
|---|---|
| Genetics | The biggest factor — height runs in families |
| Nutrition | A balanced diet supports full growth potential |
| Sleep | Growth hormone is released during deep sleep |
| Health | Chronic illness can affect growth |
| Physical activity | Supports healthy development |
How Accurate Is Height Prediction?
Mid-parental and growth-curve methods are useful estimates, not guarantees. A child's final height depends on many factors and can vary by several centimeters from the prediction. For a more precise assessment, a pediatrician can use bone-age X-rays and growth charts tracked over time.
Why Use a Height Calculator?
- Satisfy curiosity about how tall a child may become.
- Track whether growth is on a typical trajectory.
- Plan ahead for clothing and activities.
Note: This is a general estimate, not medical advice. Consult a pediatrician for concerns about growth.
Frequently Asked Questions
How do you predict a child's height?
A common method averages the parents' heights and adds 6.5 cm for boys or subtracts 6.5 cm for girls. The calculator applies this mid-parental formula.
How accurate is a height predictor?
It gives a reasonable estimate, usually within about 8.5 cm of the actual adult height, but genetics, nutrition, and health all affect the final result.
What is the biggest factor in height?
Genetics is the largest factor, which is why parents' heights are the basis for most prediction methods, followed by nutrition, sleep, and health.
Can a child grow taller than predicted?
Yes — predictions are estimates, and good nutrition, sleep, and health can help a child reach the upper end of their genetic potential.
Is this height calculator free?
Yes — it is completely free, requires no signup, and predicts adult height instantly.