Height Calculator
Convert height between feet and inches, inches, centimeters, and meters, compare two heights, find the exact height difference, estimate adult height using the mid-parental method, and use quick real-world height helpers in one clean tool.
Background
Height is commonly written in different unit systems depending on the country and context. In science and medicine, height is often measured in centimeters or meters. In everyday use in the U.S., many people write height in feet and inches. This calculator helps you switch between these systems, compare heights clearly, and understand what the numbers mean.
How to use this calculator
- Convert Height changes one height into feet plus inches, inches, centimeters, and meters.
- Compare Heights shows which height is taller and by how much.
- Height Difference gives the exact difference between two heights in multiple unit forms.
- Predict Adult Height gives a rough estimate two ways: from both parents' heights (mid-parental method), or from your own current height, age, and sex (growth-curve method) — pick whichever matches the information you have.
- Height Helper gives quick practical estimates such as eye level and standing reach.
How this calculator works
- It first converts every height into a common base unit: centimeters.
- Then it converts that value into the other common formats: ft + in, in, and m.
- The smart parser can recognize common user input styles like 5'11", 5 ft 11, 180 cm, 1.8 m, and 70 in.
- For comparisons, it subtracts one converted height from the other.
- For parent-based adult height prediction (one method under Predict Adult Height), it uses the mid-parental method with a rough target range.
- For self-based adult height prediction (the other method under Predict Adult Height), it compares current height to the typical percent of adult height reached at that age and sex, then scales up to estimate the adult value.
- For helpers, it applies simple body-proportion approximations for everyday estimates.
Formula & Equations Used
Centimeters from inches: cm = in × 2.54
Total inches from feet and inches: total in = ft × 12 + in
Centimeters from feet and inches: cm = (ft × 12 + in) × 2.54
Meters from centimeters: m = cm / 100
Height difference: difference = |height₂ − height₁|
Mid-parental height for boys: (father + mother + 13) / 2
Mid-parental height for girls: (father + mother − 13) / 2
Growth-curve adult height prediction: predicted adult height = current height ÷ (percent of adult height reached at current age)
Example Problems & Step-by-Step Solutions
Example 1 — Convert 5 ft 11 in to centimeters
- Convert feet to inches: 5 × 12 = 60.
- Add the remaining inches: 60 + 11 = 71 in.
- Convert to centimeters: 71 × 2.54 = 180.34 cm.
- So, 5 ft 11 in is 180.34 cm.
Example 2 — Compare 173 cm and 180 cm
- Both heights are already in centimeters.
- Subtract the smaller from the larger: 180 − 173 = 7 cm.
- So, 180 cm is taller by 7 cm.
Example 3 — Find the difference between 5 ft 5 in and 6 ft 2 in
- Convert both heights to inches.
- 5 ft 5 in = 65 in and 6 ft 2 in = 74 in.
- Difference: 74 − 65 = 9 in.
- So, the difference is 9 inches, or about 22.86 cm.
Example 4 — Predict adult height from parents' heights
Suppose the father is 180 cm and the mother is 165 cm.
- Add the parents' heights and 13 cm for a boy: 180 + 165 + 13 = 358.
- Divide by 2: 358 / 2 = 179 cm.
- So, the mid-parental estimate is 179 cm.
Example 5 — Predict my own adult height from current height & age
Suppose a 15-year-old girl is currently 5'6" (167.6 cm).
- At age 15, girls have typically reached about 98.9% of adult height.
- Divide current height by that percentage: 167.6 / 0.989 ≈ 169.5 cm.
- So, the growth-curve estimate is about 169.5 cm (5'6.7").
Frequently Asked Questions
Q: How many centimeters are in 1 inch?
There are exactly 2.54 centimeters in 1 inch.
Q: How do I convert feet and inches into centimeters?
First convert feet into inches, add the extra inches, then multiply the total inches by 2.54.
Q: Can I type height as 5'11" or 180 cm directly?
Yes. The smart parser can read common formats such as 5'11", 5 ft 11, 180 cm, 1.8 m, and 70 in.
Q: Is the adult height prediction exact?
No. Both the mid-parental method and the growth-curve method are rough estimates. Real adult height can vary because of genetics, nutrition, health, and growth timing.
Q: Which "Predict Adult Height" method should I use?
Use "From parents' heights" (the mid-parental method) if you know both parents' heights — it works at any age, even for a newborn. Use "From my height & age" (the growth-curve method) if you don't know or don't want to enter parent heights — it just needs the person's own current height, age, and sex, but only works while they're still growing.
Q: Should height be measured with shoes?
Usually no. For standard measurement, height is typically measured without shoes.
All calculators