Interactive calculators for many common and exotic measurement systems, including metric, Ancient Greek, Roman, and old Russian.

Twenty-three printable worksheets for elementary school-aged children. Focuses primarily on conversion of units of length.

Features printable worksheets. Includes English and Metric System pages.

Java metric conversion calculator for length, weight, pressure, and volume.

A summary of most of the units of measurement to be found in use around the world today (and a few of historical interest), together with the appropriate conversion factors needed to change them into a standard unit.

A dictionary of units of measurement: explanations of the metric system, System Internationale (SI), English customary system, and other modern measuring systems. Plus extensive links to other measurement-related Internet resources.

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

Conversion factors and online calculators for metric and imperial units.

A temperature converter for Celsius and Fahrenheit.

Online conversions from physics units to other physics units. Includes a comprehensive set of units with definitions.