Converters

Length Converter

Convert any length measurement between millimeters, centimeters, meters, kilometers, inches, feet, yards, and miles.

Enter a value above to see the conversion.

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How Length Conversion Works

Every unit is expressed as a fixed ratio to the meter — the SI base unit of length. To convert from any unit A to unit B, the value is first converted to meters, then divided by the meter factor of unit B.

result = value × (A_to_meters / B_to_meters)

Example: 100 cm → ft = 100 × (0.01 / 0.3048) ≈ 3.281 ft

Metric

  • 1 km = 1,000 m
  • 1 m = 100 cm
  • 1 cm = 10 mm

Imperial

  • 1 mi = 1,760 yd
  • 1 yd = 3 ft
  • 1 ft = 12 in

Metric vs Imperial Length Units

The metric system uses consistent powers of ten — a kilometer is 1,000 meters, a centimeter is one hundredth of a meter. This makes arithmetic straightforward and is the standard in science and most of the world.

Imperial units — inches, feet, yards, and miles — have fixed but irregular ratios (12 inches per foot, 3 feet per yard, 1,760 yards per mile). They remain common in everyday use in the United States for distances, heights, and building measurements.

Frequently asked questions

How many feet are in a meter?
One meter equals approximately 3.28084 feet. To convert meters to feet, multiply by 3.28084. To convert feet to meters, multiply by 0.3048.
How do I convert kilometers to miles?
Multiply the kilometer value by 0.621371 to get miles. For example, 10 km × 0.621371 = 6.21371 miles. To go the other way, multiply miles by 1.60934.
What is the difference between metric and imperial length units?
Metric units (mm, cm, m, km) are based on powers of 10 and are used internationally. Imperial units (in, ft, yd, mi) are primarily used in the United States and a few other countries.
How many inches are in a foot?
There are exactly 12 inches in one foot. To convert feet to inches, multiply by 12. To convert inches to feet, divide by 12 or multiply by 0.0833.
What is the base unit used for conversions?
All conversions use the meter as the base unit. Each unit is converted to meters first, then to the target unit.

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