Length Converters
One mile is 1.609344 kilometers and one inch is exactly 2.54 centimeters — the two conversions people reach for most, and both are fixed by international agreement rather than approximation. Every tool on this page uses those exact factors, so a marathon's 26.2 miles comes back as 42.195 km, not a rounded guess.
Length is the most-converted category on the site because it spans so many everyday jobs: reading a road sign abroad, sizing a room in the units your tape measure uses, translating a height between feet-and-inches and centimeters, or dropping down to the micrometers and nanometers that describe wavelengths and chip features. The 28 converters here move cleanly between metric and imperial in both directions — pick the pair you need and the reverse is one tap away.
The whole metric side is just powers of ten: a kilometer is 1,000 meters, a meter is 100 centimeters, a centimeter is 10 millimeters, so shifting scale never changes the digits, only where the decimal point sits. Imperial units don't line up so neatly — 12 inches to a foot, 3 feet to a yard, 1,760 yards to a mile — which is exactly why a converter earns its keep. Start with the popular pairs below, or scroll for the full list.
Most popular
Kilometers to Miles Converter
Convert kilometers to miles and miles to kilometers instantly.
Centimeters to Meters Converter
Convert centimeters to meters and meters to centimeters.
Feet to Millimeters
Convert feet to millimeters and back.
Kilometers to Millimeters
Convert kilometers to millimeters and back.
Micrometers to Nanometers Converter
Convert micrometers to nanometers and nanometers to micrometers.
Micrometers to Millimeters Converter
Convert micrometers to millimeters and millimeters to micrometers.
All length converters
Miles to Kilometers Converter
Convert miles to kilometers and kilometers to miles instantly.
Feet to Meters Converter
Convert feet to meters and meters to feet with precise conversion.
Inches to Centimeters Converter
Convert inches to centimeters and centimeters to inches instantly.
Kilometers to Miles Converter
Convert kilometers to miles and miles to kilometers instantly.
Centimeters to Feet Converter
Convert centimeters to feet and feet to centimeters for height conversions.
Centimeters to Meters Converter
Convert centimeters to meters and meters to centimeters.
Micrometers to Millimeters Converter
Convert micrometers to millimeters and millimeters to micrometers.
Millimeters to Micrometers Converter
Convert millimeters to micrometers and micrometers to millimeters.
Nanometers to Micrometers Converter
Convert nanometers to micrometers and micrometers to nanometers.
Micrometers to Nanometers Converter
Convert micrometers to nanometers and nanometers to micrometers.
Feet to Centimeters
Convert feet to centimeters and back.
Feet to Millimeters
Convert feet to millimeters and back.
Kilometers to Millimeters
Convert kilometers to millimeters and back.
Kilometers to Nanometers
Convert kilometers to nanometers and back.
Kilometers to Yards
Convert kilometers to yards and back.
Micrometers to Centimeters
Convert micrometers to centimeters and back.
Micrometers to Feet
Convert micrometers to feet and back.
Micrometers to Miles
Convert micrometers to miles and back.
Miles to Nanometers
Convert miles to nanometers and back.
Millimeters to Centimeters
Convert millimeters to centimeters and back.
Millimeters to Feet
Convert millimeters to feet and back.
Millimeters to Kilometers
Convert millimeters to kilometers and back.
Millimeters to Nanometers
Convert millimeters to nanometers and back.
Nanometers to Feet
Convert nanometers to feet and back.
Nanometers to Kilometers
Convert nanometers to kilometers and back.
Nanometers to Meters
Convert nanometers to meters and back.
Nanometers to Miles
Convert nanometers to miles and back.
Nanometers to Millimeters
Convert nanometers to millimeters and back.