1. Total Father Height: '+fTotal+' inches
2. Total Mother Height: '+mTotal+' inches
3. Applying '+gender+' formula: (Father + Mother '+(gender==='boy'?'+':'-')+' 5) / 2
4. ('+fTotal+' + '+mTotal+' '+(gender==='boy'?'+':'-')+' 5) / 2 = '+predicted+' inches';}}else{var cmVal=parseFloat(document.getElementById('cm_input').value);if(isNaN(cmVal)){alert('Please enter a valid centimeter value');return;}var totalInches=cmVal/2.54;var feet=Math.floor(totalInches/12);var inches=Math.round((totalInches%12)*10)/10;resText.innerHTML='Converted Height: '+feet+' ft '+inches+' in';}}
Calculator Use
This height calculator is a multi-purpose tool designed to help parents estimate their child's future adult height and assist individuals in converting height measurements between metric (centimeters) and imperial (feet and inches) units. By using the scientifically recognized Mid-Parental Height method, also known as the Tanner Method, you can get a statistical projection of how tall a child might grow based on genetic potential.
Whether you are tracking a growth spurt or just curious about genetics, this calculator provides quick results with optional step-by-step mathematical breakdowns.
- Father's Height
- The biological father's height in feet and inches. Genetics from the paternal side account for roughly 50% of the inheritable height traits.
- Mother's Height
- The biological mother's height. Maternal height is equally critical in determining the mid-parental average.
- Child's Gender
- Biological sex plays a significant role in final height due to differences in bone density and the timing of puberty. Boys generally receive a 5-inch (13cm) statistical adjustment upward from the parental average.
How It Works
The height calculator uses the Mid-Parental Height formula. This method assumes that a child's height will likely fall near the average height of their two biological parents, adjusted for sex. While nutrition, health, and environment play roles, roughly 60% to 80% of height is determined by DNA.
Boy's Height = (Father's Height + Mother's Height + 5 inches) / 2
Girl's Height = (Father's Height + Mother's Height – 5 inches) / 2
- Step 1: Convert all measurements into a single unit (total inches).
- Step 2: Add the father's and mother's heights together.
- Step 3: Add 5 inches for a boy or subtract 5 inches for a girl.
- Step 4: Divide the total by two to find the mean.
Calculation Example
Example: Let's calculate the predicted height for a boy whose father is 6'0″ (72 inches) and mother is 5'4″ (64 inches).
Step-by-step solution:
- Father Height = 72 inches
- Mother Height = 64 inches
- Sum = 72 + 64 = 136 inches
- Adjustment for Boy = 136 + 5 = 141 inches
- Divide by 2 = 141 / 2 = 70.5 inches
- Final Result: 5 feet 10.5 inches
Common Questions
How accurate is this height calculator?
While based on proven statistical models, the Mid-Parental method has a margin of error of about 4 inches in either direction. This is because genetics involve many different genes (polygenic trait), and environmental factors like nutrition during childhood can significantly impact whether a child reaches their full genetic potential.
When do children stop growing?
Generally, girls stop growing about two years after their first menstrual period, typically between ages 14 and 16. Boys tend to grow until age 18, though some continue to see minor increases in height into their early 20s as their growth plates finally close.
Can nutrition change the result?
Yes. Chronic malnutrition or serious illness during the peak growth years can lead to stunted growth. Conversely, a diet rich in protein, calcium, and Vitamin D helps ensure a child reaches the maximum height predicted by the height calculator.
What is the "Two-Year-Old" method?
Another popular method is to simply double the height of a child at age two for boys, or at age 18 months for girls. This is often surprisingly accurate but relies on having exact measurements at those specific developmental milestones.