Quick answer: With a 175 cm father and a 160 cm mother, a boy's target height is (175 + 160 + 13) ÷ 2 = 174 cm, and most boys of such parents end up between 165.5 and 182.5 cm.
How it's calculated
Mid-parental height (Tanner's method): for a boy, (father's height + mother's height + 13 cm) ÷ 2; for a girl, (father's height + mother's height − 13 cm) ÷ 2. The 13 cm is the average difference in adult height between men and women.
The target range is the result ± 8.5 cm, which covers roughly the 3rd to 97th centile: most children land somewhere inside it.
The method uses only the parents' heights. It cannot see a child's own growth so far, nutrition, illness or the timing of puberty, and it tends to overestimate for very tall parents and underestimate for very short ones. A doctor tracking the child on a growth chart, and bone age where needed, gives a closer forecast.
Worked examples
- Father 175 cm, mother 160 cm, boy: (175 + 160 + 13) ÷ 2 = 174 cm (165.5 – 182.5)
- Same parents, girl: (175 + 160 − 13) ÷ 2 = 161 cm (152.5 – 169.5)
- Father 5 ft 9 in, mother 5 ft 3 in, boy: (175.26 + 160.02 + 13) ÷ 2 = 174.1 cm ≈ 5 ft 8.5 in
Frequently asked questions
How accurate is the mid-parental height?
It is a rough guide. Most children end up within about 8.5 cm of it, but a single child can be anywhere in that range.
Can a child be taller than both parents?
Yes. Better nutrition and health from one generation to the next, and normal genetic variation, mean many children outgrow their parents.
When should I ask a doctor about my child's height?
If the child's growth crosses centile lines on the growth chart, or their height is far from the target range for their age, a paediatrician can check growth properly.
At what age do children reach their adult height?
Most girls stop growing at around 15 or 16, and most boys at 17 or 18, a year or two after puberty ends. Some boys keep growing a little after that.
Can I use this for an adopted child?
Not really. It's based on the biological parents' heights, so without them the estimate means very little. Your paediatrician can follow the child's growth on a chart instead.
Is there a more accurate way to predict adult height?
Doctors can X-ray the hand and wrist to check bone age, which shows how much growing is left. It's more precise than parents' heights, but it needs a medical visit.