# Height Calculator

> Estimate a child’s adult target height and likely range from both parents’ heights with the mid-parental height method of Tanner et al.

Category: Everyday tools · Applies to: Worldwide · Last updated: 2026-10-29
Interactive calculator: https://calculators.geekmidst.com/calculators/height-calculator

Children tend to grow towards the average of their parents’ heights, adjusted for sex. This gives a target height and a range that covers most children, not a precise forecast.

Also called: Child height predictor, Mid-parental height calculator.

## Inputs
- Child (options: Boy, Girl; default boy)
- Heights in (options: cm, inches; default cm)
- Father’s height (default 180)
- Mother’s height (default 165)

## Results
- Target adult height
- In feet and inches
- In inches
- Likely range from
- Likely range to

## Formula

```
Boy: (Father + Mother + 13 cm) ÷ 2;  Girl: (Father + Mother − 13 cm) ÷ 2;  Range: target ± 8.5 cm
```

Where:
- 13 cm (5.12 in): average difference between adult male and female height
- 8.5 cm: about two standard deviations either side of the target

## Worked example
1. Add the parents’ heights: 180 + 165 = 345 cm.
2. For a boy add 13 cm and halve: (345 + 13) ÷ 2 = 179 cm.
3. Range: 179 − 8.5 = 170.5 cm to 179 + 8.5 = 187.5 cm.

**Result:** A boy whose parents are 180 cm and 165 cm has a target adult height of about 179 cm (5 ft 10.5 in), most likely between 170.5 and 187.5 cm.

## What the result means

The target is where a child’s growth would be expected to head given the parents’ heights. Many children end up a few centimetres from it, and some outside the range. A child whose growth is moving well away from their target range is worth discussing with a doctor, who will use growth charts and other measurements.

## Assumptions and limits
- Mid-parental (target) height method of Tanner, Goldstein and Whitehouse (1970), as presented by the MSD Manual.
- Both parents’ adult heights are measured, not estimated.
- The child’s growth is not affected by illness, nutrition problems or medication.
- It does not use the child’s own height, age or bone age, so it cannot detect early or late growth.
- It works less well when parents’ heights are very different or unusually tall or short.

## Questions

### How accurate is it?

The ±8.5 cm range covers roughly 95% of children whose growth is typical. Methods that also use the child’s current height and bone age, done in a clinic, are more precise.

### Can I use inches?

Yes. Choose inches; the method is the same with 5.12 in in place of 13 cm.

## Sources
- [MSD Manual: Height potential (mid-parental height) calculator](https://www.msdmanuals.com/iframe/manual/medical-calculators/heightpotential.htm)

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_This is a general screening estimate for adults, not medical advice or a diagnosis. Talk to a qualified health professional about your health._

Source: GM¹X CalcVerse — https://calculators.geekmidst.com/calculators/height-calculator