Conversions and equivalences of the principal units of measure of the SI and Anglo-Saxon systems.

Factsheets, regulations and conversion tools. Official site of the United States Metric Program.

Pressure group campaigning for the completion of metrication in the UK. History, legislation, and practical help.

Conversion factors and online calculators for metric and imperial units.

Simple Celsius-Fahrenheit conversions.

Catalogue of traditional British units with historical notes.

Outline of the metric system with emphasis on applications in physics.

Pressure group opposing compulsory metrication. Political, consumer and transport information, discussion boards and links.

Standard-to-metric conversion factor tables with definitions, derived units and prefixes.

Converts common measurements from metric to imperial and vice versa, with other systems included for selected quantities such as light years, picas, and Old Russian measures.