Length Converter

Convert between millimeters, centimeters, meters, kilometers, inches, feet, yards, miles, and nautical miles.

About this Calculator

Convert between millimeters, centimeters, meters, kilometers, inches, feet, yards, miles, and nautical miles.

Formula & Calculations

Formula

Result = Input value × (Conversion factor from unit / Conversion factor to unit), normalized to meters

Where:

mm=Millimeters (1 mm = 0.001 m)
cm=Centimeters (1 cm = 0.01 m)
m=Meters (base unit)
km=Kilometers (1 km = 1000 m)
in=Inches (1 in = 0.0254 m)
ft=Feet (1 ft = 0.3048 m)
yd=Yards (1 yd = 0.9144 m)
mi=Miles (1 mi = 1609.344 m)
nmi=Nautical miles (1 nmi = 1852 m)

Assumptions

All conversions use standard international definitions.
The meter is used as the intermediate base unit for all calculations.
Nautical miles follow the international standard of exactly 1,852 meters.

Calculation Examples

Example 1

Inputs:5 miles to kilometers

Result:8.04672 km

5 × 1609.344 ÷ 1000 = 8.04672 km.

Example 2

Inputs:100 centimeters to inches

Result:39.3701 in

100 × 0.01 ÷ 0.0254 = 39.3701 in.

Example 3

Inputs:1 nautical mile to meters

Result:1852 m

1 × 1852 = 1852 m.

Frequently Asked Questions

What is a nautical mile?

A nautical mile is based on the Earth's circumference and equals exactly 1,852 meters. It is used in maritime and aviation navigation. One nautical mile equals approximately 1.1508 statute miles.

Can I convert between metric and imperial length units?

Yes. All listed units — metric (mm, cm, m, km) and imperial/US (in, ft, yd, mi) plus nautical miles — are fully supported in both directions.