Predict a child's adult height using the Khamis-Roche method or mid-parental formula, plus a height unit converter
⚠️
🧬
Khamis-Roche Height Predictor
The most accurate non-skeletal method for predicting a child's adult height. Uses child's current age, height, weight, and both parents' heights. Valid for ages 4–17.5 years.
♂ Boy
♀ Girl
Feet
Inches
Centimeters
Feet
Inches
Centimeters
Feet
Inches
Centimeters
Predicted Adult Height
5′ 9″
175 cm
±2.1 inches margin of error
Predicted (ft)
—
Predicted (cm)
—
Low Range
—
High Range
—
📏 Predicted Height Range
———
Khamis-Roche Formula Applied
—
📊 Result Summary
—
ℹ️ About This Method
The Khamis-Roche method (1994) is the most accurate non-skeletal height predictor. It uses the child's current height, weight, age, and mid-parent height. It is most applicable to Caucasian children ages 4–17.5 free from growth disorders. Margin of error: ±2.1 inches for boys, ±1.7 inches for girls.
⚠️
👨👩👧
Mid-Parental Height Formula
Predict a child's height based on parents' heights only. Ideal for unborn children or infants. Margin of error: ±4 inches (±10 cm).
♂ Boy
♀ Girl
Feet
Inches
Centimeters
Feet
Inches
Centimeters
Predicted Adult Height
5′ 9″
175 cm
±4 inches (±10 cm) margin of error
Predicted (ft)
—
Predicted (cm)
—
Low Range
—
High Range
—
Mid-Parental Formula Applied
—
📊 Result Summary
—
ℹ️ Mid-Parental Formula
Mid-parental height = (mother + father) ÷ 2 Boy's predicted height = mid-parental + 2.5 inches (6.5 cm) Girl's predicted height = mid-parental − 2.5 inches (6.5 cm)
Margin of error: ±4 inches (±10 cm). This simple method is less accurate than Khamis-Roche.
📐
Height Unit Converter
Convert height between feet & inches (imperial) and centimeters (metric).
Feet & Inches → Centimeters
cm
⇄
Centimeters → Feet & Inches
ft in
📐 Conversion Formula
1 foot = 12 inches = 30.48 cm | 1 inch = 2.54 cm
To convert: cm = (feet × 12 + inches) × 2.54 | inches = cm ÷ 2.54
📊
Average Height by Age (CDC Data)
Median heights for boys and girls by age according to CDC growth charts. Use this to compare your child's height to the national average.
Age
♂ Boys (ft)
♂ Boys (cm)
♀ Girls (ft)
♀ Girls (cm)
4 years
3′ 4″
102
3′ 3″
101
6 years
3′ 9.5″
115.5
3′ 9″
115
8 years
4′ 2″
128
4′ 2″
127.5
10 years
4′ 6.5″
138.5
4′ 7″
138.6
12 years
4′ 11″
149
4′ 11.5″
151.5
13 years
5′ 1″
154.9
5′ 1.5″
155.4
14 years
5′ 4″
162.4
5′ 3″
159.8
16 years
5′ 8.5″
173.5
5′ 4″
162.5
18 years
5′ 9.5″
176
5′ 4″
163
20 years
5′ 9.5″
177
5′ 5″
163
📈 Key Growth Facts
Girls typically stop growing at 14–15 years old (about 2 years after first menstruation). Average adult female height: 5′ 5″ (163 cm). Boys stop growing around 16–18 years old (about 4 years after puberty begins). Average adult male height: 5′ 9″ (177 cm).
Height is 60–80% determined by genetics, with nutrition and environment accounting for the remaining 20–40%.
⚠️ Important Note
These are median values from CDC growth charts for U.S. children. Individual heights can vary significantly. If you are concerned about your child's growth, consult a pediatrician.