Mid-Parental Height Calculator (How Tall Will My Child Be?)
A prediction of your child's adult height from both parents' heights, using Tanner's mid-parental formula, with a likely range.
Results
What this tool does
The mid-parental, or target, height averages the parents' heights after correcting for the roughly 13 cm by which men are taller than women on average: add 13 cm to the parents' sum for a boy, subtract it for a girl, then halve. It comes from work by James Tanner and colleagues in 1970. About 95 % of children are expected to end up within roughly 8.5 cm of it, which is a wide margin, and genes from earlier generations, nutrition, illness and the pace of puberty all move the real figure. A child whose growth chart keeps drifting away from the family range is worth mentioning to a paediatrician.
Formula
boys: (father + mother + 13 cm) ÷ 2 · girls: (father + mother − 13 cm) ÷ 2 · range ± 8.5 cm (Tanner)
Variables
| Symbol | Meaning | Unit |
|---|---|---|
fh | Father's height | cm |
mh | Mother's height | cm |
sx | The child is | — |
TH | Predicted adult height (mid-parental) | cm |
LO | Likely range: from | cm |
HI | Likely range: up to | cm |
Worked example
- Father's height178 cm
- Mother's height165 cm
- The child is1
- Predicted adult height (mid-parental)178.0 cm
- Likely range: from169.5 cm
- Likely range: up to186.5 cm
Limitations
- This tool is informational only. It does not diagnose, treat or replace a qualified health professional. Speak to a doctor before making decisions about your health.
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.