There are different types of Leagues

There are a few different types of League. On this site we have conversions for US Leagues and UK Leagues. In addition, there are also Nautical Leagues which can be found on this site. Please either select the appropriate unit on the selection above of click the required unit in the links below:

US Leagues

UK Leagues

Nautical Leagues

What is a millimeter?

A millimeter is a thousandth of a meter (1/1000) which is the SI (International System of Units) unit of length. It is normally used to measure small lengths like the thickness of a sheet of paper or the dimensions of a small object.

One millimeter is approximately equal to 0.03937 inches (about 1/25th). Presicely there are 25.4 millimeters in an inch and it is often used in science and engineering. It is used in countries that have adopted the metric system.

You may come across millimeters when measuring the size of electronic components, jewelry or even the thickness of a fingernail.

What is a League?

A league was originally roughly the distance a person could walk in an hour, about 3 miles (4.8 kilometers). The exact length varied with the country and the period.

A league is an old unit of length, usually around 3 miles or 5 kilometers, though the exact figure varied by country and period. Jules Verne's Twenty Thousand Leagues Under the Sea is about distance travelled, not depth – 20,000 of his 4 kilometer leagues is 80,000 kilometers, twice around the Earth.