What this calculator does
Mid-parental height prediction works out predicted adult height for a child from both parents heights (Tanner method). Enter your own figures above and the answer updates as you type: nothing is fixed in the code, so the result reflects exactly the numbers you supply.
The formula this calculator evaluates is printed under the tool and explained below, so you can check the working by hand or reuse it in a spreadsheet.
The formula
FormulaBoys: (mother + father + 13) / 2 cm. Girls: (mother + father − 13) / 2 cm. Typical range ± 10 cm.
The inputs explained
| Field | What to enter |
|---|---|
| Mother’s height (cm) | A number, measured in cm. Starts at 165. |
| Father’s height (cm) | A number, measured in cm. Starts at 178. |
| Child’s sex | Choose from Boy, Girl. |
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How the answer changes with mother’s height
Every other input is held at the calculator’s starting values while mother’s height varies. Select any row to load that scenario into the calculator.
How the answer changes with mother’s height