Estimate a child’s likely adult height using the mid-parental height method, based on both parents’ heights.
The Child Height Predictor Calculator uses the mid-parental height method, a well-known formula that estimates a child’s likely adult height from both parents’ heights.
This method gives a reasonable ballpark estimate, but actual adult height depends on genetics, nutrition, and health during growth — the true result commonly falls within about 4 inches of the estimate.
Boys: (Father’s Height + Mother’s Height + 5) ÷ 2. Girls: (Father’s Height + Mother’s Height − 5) ÷ 2. Result is in inches.
For a father at 70 in and mother at 64 in, a son is predicted to reach about 69.5 in, while a daughter is predicted to reach about 64.5 in.
A common method (the mid-parental height formula) averages both parents' heights, adjusting up or down slightly depending on the child's sex.
It's a rough statistical estimate — actual adult height depends on genetics, nutrition, and health factors beyond parental height, so real results can vary by several inches.
Predictions based on a child's current growth pattern (bone age X-rays used by doctors) become more reliable closer to puberty than simple parental-height formulas used for young children.