Japeters Unit Conversion is a complex unit conversion application. An easy-to-use application that can help you convert values from one set of measurements to another. Simple to use, but with advanced features including a molecular weight calculator, the program includes both standalone and MS Excel versions.
Behind its simple interface, Unit Conversion includes a flexible parser that allows an infinite number of combinations of units to be evaluated and processed. Unit Conversion allows the user to easily add new units to its database.

Please Note: Can be used indefinitely for home or non-profit use

The license of this software is Free Trial Software, the price is $19.99, you can free download and get a free trial.