Scales

Scales is a unit converter which converts over 300 pre-installed units in a simple interface.
It has a fully customisable units database so you can add your own units, edit, re-arrange and delete both units and their categories in which they are organised.
Just select a category, choose a unit to convert to and from, enter the value to convert and the result updates in real time, as you type.
No time to look for the unit?

No problem. Just hit cmd+F or click on the search bar & begin typing the name of a unit. Scales will display the search units along with what category they are in.
Features:
-Fully editable database of units
-Search all units with the search bar
-Scientific notation for very large or very small numbers
-Option to use commas to separate thousands
-Option to keep window on top of all others
Please check website for more details.