Length Converter

How length conversion works

Every length converts through one shared base unit - the meter. Each unit has a fixed factor to meters: an inch is 0.0254 m, a foot is 0.3048 m, a mile is 1,609.344 m. To convert, you turn your value into meters, then divide by the target unit's factor. So 100 cm becomes 1 m, then 1 / 0.0254 = 39.37 inches. The tool does both steps for you and shows the result the instant you type.

Worked examples

• How tall is 180 cm in feet? 180 cm is 1.8 m, and 1.8 / 0.3048 = 5.91 ft, or about 5 ft 11 in.
• How far is a 10K in miles? 10 km / 1.609 = 6.21 miles.
• Screen size: a 15-inch laptop is 15 x 2.54 = 38.1 cm on the diagonal.

Metric and imperial at a glance

The metric system scales in tens - 10 mm to a cm, 100 cm to a meter, 1,000 m to a kilometer - so shifting units is just moving a decimal point. Imperial units use older ratios: 12 inches to a foot, 3 feet to a yard, 1,760 yards to a mile. That is why the two rarely line up neatly, and why a quick converter beats mental arithmetic. Keep the reference table above handy for the conversions people look up most.

Working with other measurements? Try the weight converter for kg and pounds, the speed converter for mph and km/h, or the all-in-one unit converter for area, volume and more. For screen and video dimensions, the aspect ratio calculator keeps proportions intact.

Popular conversions

• centimeters to inches (cm to in) - 1 cm = 0.393701 in
• inches to centimeters (in to cm) - 1 in = 2.54 cm
• feet to meters (ft to m) - 1 ft = 0.3048 m
• meters to feet (m to ft) - 1 m = 3.28084 ft
• miles to kilometers (mi to km) - 1 mi = 1.60934 km
• kilometers to miles (km to mi) - 1 km = 0.621371 mi
• millimeters to inches (mm to in) - 1 mm = 0.0393701 in
• inches to millimeters (in to mm) - 1 in = 25.4 mm

Frequently asked questions