Kilometers to Feet Converter

The kilometer is exactly 1,000 meters, the unit of length in the International System used for distances between places rather than across a room. It is written km and is the basis of the metric road network.

Road signs, speed limits, odometers and race distances use kilometers in most of the world. Maps quote distances in kilometers, and athletic events such as the marathon are described in kilometers.

One kilometer equals 0.621371 miles, an exact conversion from the definition of the mile as 1,609.344 meters. The displayed figure is rounded, so converting kilometers to miles and back may shift the last digit.

Mixing meters and kilometers is the usual error: a walking route given as 4,000 meters is four kilometers, not forty. A kilometer is also a length unit, so square kilometers measure area.

Kilometers and miles both measure road distance, while meters measure shorter spans inside the same journey. Treating a mile figure as kilometers understates the distance by about a third, and mixing the two within one route confuses every later step.

The foot is exactly 0.3048 meters, or twelve inches. United States survey work has used a separate survey foot, defined as 1200/3937 meters and equal to about 0.3048006 meters.

Aviation uses feet for altitude and flight levels worldwide, even in countries that measure road distance in kilometers. Building heights, room dimensions, timber and, in some places, body height are also quoted in feet.

The metric conversion is exact, since the foot is defined as 0.3048 meters, and the reverse is exact too. A displayed result is rounded to six decimal places at most, so a round trip can differ in the final digit.

The common slip is assuming a foot is close to a third of a meter when it is slightly longer, so rough mental division undershoots. Feet also belong to length, while square feet measure area and cubic feet measure volume.

The foot competes with the meter for height and building dimensions and with the inch for small spans. Because one meter is a little over three feet, treating a meter figure as feet overstates a dimension more than threefold.