Calcoid
Conversions

Length Converter

Convert between metric and imperial length units. Switch between mm, cm, m, km, inches, feet, yards, and miles instantly.

Convert

Millimeters

30,480 mm

Centimeters

3,048 cm

Meters

30.48 m

Kilometers

0.03048 km

Inches

1,200 in

Feet

100 ft

Yards

33.3333 yd

Miles

0.018939 mi

Length Conversion Table

CentimetersInchesFeet
1 cm0.390.03
5 cm1.970.16
10 cm3.940.33
20 cm7.870.66
30 cm11.810.98
50 cm19.691.64
100 cm39.373.28
150 cm59.064.92
200 cm78.746.56

Frequently Asked Questions about the Length Converter

How many meters are in a foot?
1 foot equals exactly 0.3048 meters, a fixed international standard. Flip it around: 1 meter is about 3.28084 feet, or 39.370079 inches. The calculator uses these exact constants and rounds each result to six decimal places.
How long is a mile in kilometers?
1 mile equals exactly 1.609344 kilometers. A 5K race works out to about 3.1069 miles, and 10 miles is roughly 16.09 km. The calculator applies the full 1.609344 factor, not a rounded approximation, so longer distances stay accurate.
How do I convert meters to yards quickly?
Divide meters by 0.9144, or multiply by about 1.0936. A 100-meter sprint is 109.36 yards, just over 109 and a bit shy of 110. For rough field estimates, 100 m is close to 100 yards plus one-tenth of that distance.
Where are metric vs. imperial length units used?
Metric units (millimeters, centimeters, meters, and kilometers) are the global standard for science, manufacturing, and everyday measurement in most countries. The US relies on inches, feet, yards, and miles for daily life, construction, and road distances. The UK uses miles and yards on road signs but meters and centimeters for most other contexts.
What is a quick shortcut to estimate inches from centimeters?
Divide by 2.54, the exact conversion the calculator uses. A 30 cm ruler is 11.81 inches. For a mental shortcut, divide by 2.5 and then subtract about 1.6%, which gets you within a quarter-inch on most everyday measurements.