Metric Master

MetricMaster is a measurement unit conversion calculator containing 2,000 metric/S.I., imperial, U.S., and other units in its database, most to 14 significant digit precision. New units can be added and unwanted ones removed. Supports ft/in/fractions, different number formats including scientific notation, and complete control of significant digits. MetricMaster can also convert currencies, clock times, and many physical constants. On-line info is available on the history and development of modern measurement systems. 600 of the units have full definitions. For OS 8, 9, and X.