The Richwood Report

Here is a good unit conversion site with emphasis on British units. If you run into a reference to some little-known measurement from the UK, it will probably be explained on this site. For example, here are units of capacity and here are old units for specific commodities. Use of these units in trade is actually illegal, I understand, in the UK because only metric system units are legal for trade. You can choose conversion factors for ordinary units from the category index or use drop-down menus here.