Length Converter

From engineering bridges to measuring standard paper sizes, length is the most fundamental dimension in physics and daily life. Yet, the world is divided between two major systems: the Imperial System (used in the US, Liberia, and Myanmar) and the Metric System (used extensively by the rest of the world and the scientific community).

Why Do We Have Multiple Systems?

Historically, units of length were based on the human body. An "inch" was the width of a thumb, a "foot" was actual foot length, and a "yard" was a stride. While practical for trading in local markets, this lacked precision.

The Metric System, born during the French Revolution, standardized measurement using decimal-based units derived from the Earth's circumference. Today, the meter is defined even more precisely by the speed of light: the distance light travels in vacuum in 1/299,792,458 of a second.

Specialized Units

Beyond feet and meters, our converter handles specialized fields:

• Physics & Nanotech Angstroms (Å) and Nanometers (nm) measure atoms and light wavelengths. 1 nm is one-billionth of a meter.
• Astronomy Light Years and Parsecs measure the vast emptiness of space. One Light Year is approx. 9.46 trillion kilometers.
• Nautical Nautical Miles are used in aviation and maritime navigation, based on one minute of latitude.