Our free child height predictor uses the mid-parental height method, a simple formula that paediatricians use to compare a child’s growth with their family’s genetic potential. It works in centimetres or feet and inches and shows the result in both.

Genes explain much of adult height, but nutrition, sleep, physical activity, health conditions and the timing of puberty also matter. The height predictor gives a reasonable estimate for most children, not a guarantee. If you are worried about your child’s growth, talk to your paediatrician, who can track growth on a chart over time.

How the Height Predictor Works

• Boys: (father’s height + mother’s height + 13 cm) ÷ 2
• Girls: (father’s height + mother’s height − 13 cm) ÷ 2
• Expected range: the result plus or minus about 8.5 cm, which covers most children.

The 13 cm adjustment reflects the average height difference between adult men and women. In inches, use 5 inches instead of 13 cm.

Worked Examples

How to Use the Child Height Predictor

Use the height predictor in four quick steps.

Step 1: Choose Units and Your Child’s Gender

Select Metric (cm) or Imperial (ft/in), then choose Boy or Girl.

Step 2: Enter the Father’s and Mother’s Heights

Type each biological parent’s adult height. Use measured heights where possible for a better estimate.

Step 3: Read the Estimated Adult Height

Click Predict Height. The main card shows the predicted adult height in centimetres and in feet and inches.

Step 4: Check the Expected Growth Range

Below the estimate you will see the range most children fall into, for example 169 to 186 cm.

What Affects How Tall a Child Grows?

• Genetics: the strongest factor, captured by the parents’ heights.
• Nutrition: enough protein, calcium, vitamin D and overall calories.
• Sleep: growth hormone is released mainly during deep sleep.
• Health: chronic illness, hormone problems or some medicines can affect growth.
• Puberty timing: early or late puberty changes when growth spurts happen, not usually final height.

When to Talk to a Doctor

Contact your child’s doctor if your child is much shorter or taller than others the same age, if growth seems to stop or slow sharply, or if puberty starts very early or very late. Doctors use growth charts and sometimes a bone age X-ray for a more precise prediction than any online height predictor.

Why Use a Child Height Predictor?

Parents are often curious about how tall their children will be. A height predictor gives a quick, evidence-based answer and a sensible range, helping you set realistic expectations and notice if a child’s growth seems far from their family pattern.

Height Predictor Methods Compared

For everyday curiosity, the mid-parental height predictor is the simplest option. For medical decisions, a doctor will combine growth charts with clinical checks.

Frequently Asked Questions