The Height Calculator predicts a child's adult height from the parents' heights using the mid-parental height method.
Predicted adult height: 5 ft 10.1 in (177.9 cm)
| Predicted adult height | 5 ft 10.1 in (177.9 cm) |
| Likely range (±10 cm) | 5 ft 6.1 in (167.9 cm) – 6 ft 2.0 in (187.9 cm) |
A child's adult height depends mostly on genetics, so parents' heights give the best simple prediction. Nutrition, sleep, health and hormones also play a role, and children grow at different speeds, so any prediction has a margin of error.
Add the mother's and father's heights. For a boy, add 13 cm (5 inches) and divide by 2; for a girl, subtract 13 cm and divide by 2. About two-thirds of children end up within about 5 cm and most within 10 cm of this value.
Worked example (defaults): mother 5 ft 5 in (165.1 cm), father 5 ft 10 in (177.8 cm), boy: (165.1 + 177.8 + 13) ÷ 2 = 178 cm, about 5 ft 10 in.
The Khamis-Roche method adds the child's current height and weight and is a little more accurate for children aged 4 to 17. Doubling a boy's height at age 2 or a girl's at 18 months is a popular rough rule. A bone-age X-ray assessed by a doctor is the most accurate.
If a child falls off their growth curve, grows much more slowly than peers, or starts puberty unusually early or late, talk to a paediatrician.
When do children stop growing? Girls usually around 14–16, boys around 16–18.
Can diet increase height? Good nutrition helps reach genetic potential but cannot exceed it.
Is the prediction guaranteed? No, it is an estimate.