J. Brent Dunn, Company Inc.
This spreadsheet contains the most used paper math conversion formulas for units and pricing. You can download this and put it on your computer so that it will not be necessary to connect to my website each time you want to convert an item. In newer versions of Excel, you may have to click on "enable editing" before you will be able to enter data. If you download it to your computer, it should work without having to give permission to edit the file.