Work out height prediction from parents instantly with clear inputs, formula shown and shareable results.
The mid-parental method averages the parents' heights then adds 6.5 cm for a boy or subtracts 6.5 cm for a girl. With a 165 cm mother and 180 cm father, a boy is predicted at 179 cm and a girl at 166 cm. The 95% prediction interval is about 8.5 cm either side, so it indicates a range rather than a target.
Mid-parental height
mid = (mother + father) / 2
Prediction
boys: mid + 6.5 cm; girls: mid - 6.5 cm
These figures are population-average estimates, not a medical assessment or diagnosis. Body composition equations carry errors of several percentage points, and healthy ranges vary with age, ethnicity, muscularity and medical history. Discuss weight or body composition goals with a qualified clinician or dietitian.
The prediction interval is roughly plus or minus 8.5 cm, so it identifies a likely range. Bone age radiography is far more precise.
It is half the average adult height difference between men and women, applied to shift the parental average to the child's sex.