What this calculator does
This tool converts a height expressed in feet and inches into centimeters (and meters). It is perfect for filling out forms, comparing heights between the imperial and metric systems, or working with measurements where one country uses feet/inches and another uses centimeters.
How to use it
Enter the feet portion of the height in the first box and the inches portion in the second box. Inches can include a decimal (for example 9.5). Click calculate to see the height in centimeters, along with the total number of inches and the equivalent in meters.
The formula explained
One inch is defined as exactly 2.54 centimeters, and one foot equals 12 inches. So the conversion first turns the height into total inches and then scales by 2.54:
$$\text{cm} = \left(\text{feet} \times 12 + \text{inches}\right) \times 2.54$$
Because the inch is defined exactly, this conversion is precise rather than an approximation.
Worked example
Suppose a person is 5 feet 9 inches tall. First, total inches = \(5 \times 12 + 9 = 69\) inches. Then $$\text{cm} = 69 \times 2.54 = 175.26 \text{ cm},$$ which is about 1.7526 meters.
FAQ
Is the 2.54 factor exact? Yes. Since 1959 the international inch has been defined as exactly 2.54 cm, so the result is exact for the values you enter.
Can I enter decimal inches? Yes — for example 5 ft 8.5 in works fine. The inches field accepts decimals.
How do I convert back? Divide the centimeters by 2.54 to get total inches, then divide by 12 for feet (the remainder is the inches).
