Reference

Provides calculations of various types including metric conversion, engineering calculations, and computing finance loan payments. Also, has list of general math formulas.

Generates an equivalency table from any engineering unit to any other.

A site promoting the metric system which argues why metric is better and English is worse. Provides an English-metric online calculator.

Converts many units of measurement using a JavaScript 1.1 applet.

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

Conversion factors and online calculators for metric and imperial units.

Offers conversion tools for length, volume, temperature, astronomical, clothing sizes, computer bytes, cooking measurements, time zones, density, energy, finance, flow rates, force frequency, and some fun pages.

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

Official imperial-to-metric conversion tables.

Dictionary of metric units explaining the principles and history of the system.