Length Converter

This length converter is a tool that enables quick conversion between length units in both imperial and metric, but not only that. It's equipped with twenty different units of length measurement:

ångström (Å)
picometers (pm)
nanometers (nm)
micrometers (μm)
millimeters (mm)
centimeters (cm)
decimeters (dm)
meters (m)
meters and centimeters
kilometers (km)
thousandths of an inch (mil / thou)
inches (in)
feet (ft)
feet and inches
yards (yd)
miles (mi)
nautical miles (nmi)
Sun radii (R☉)
light years (ly)
astronomical units (au)
parsecs (pc)
This length conversion calculator works by typing units (up to 11 in the same calculation) into the tool. The length converter then returns your results in each unit in real time. Click on the unit name if you want to perform length conversion to a different unit than the default ones chosen by the Omni team.

Once you've mastered lengths and their conversion, you can apply that knowledge to circles in our circle length calculator. If you are looking to convert between units of area, another tool we would recommend is the square footage calculator.

Metric measurements

A meter has been officially defined to be the distance traveled by light in a vacuum in 1/299,792,458 second. All other length and distance measurements in the metric system derive from the meter (eg. km= 1000m, 1m= 1000mm).

Imperial / American measurements

These measurements have a less logical progression. A yard can be defined as the length of a pendulum that causes its arc to swing in exactly 1 second. The Nautical mile is the distance across 1' (1/60 of a degree) around the earths surface.