Mid-Parental Height

Mid-parental height can be determined in inches or centimeters using the following calculations:

For girls: [(Father's height – 5 inches) + Mother's height] divided by 2

For boys: [(Mother's height + 5 inches) + Father's height] divided by 2

1 standard deviation (SD) = 2 inches

2 SD = 4 inches

Target height range = mid-parental height ± 4 inches

1 inch = 2.54 cm

For girls: [(Father's height – 13 cm) + Mother's height] divided by 2

For boys: [(Mother's height + 13 inches) + Father's height] divided by 2

1 standard deviation (SD) = 5.1 cm (many clinicians round to 5)

2 SD = 10.2 cm (rounded to 10 cm)

Target height range = mid-parental height ± 10.2 cm

Ninety-five percent of children have a predicted adult height that is within 4 inches above or below this mid-parental height calculation.