A conversion chart having a transparent base sheet with a first series of divergent solid lines and a second series of divergent broken lines, with the first and second series of lines having a common base line. The first series of divergent lines are spaced along any perpendicular to the base line an integral number of units in an English system of units, such as feet or pounds mass and the broken lines are spaced along any perpendicular to a base line an integral number of corresponding units in a metric system of units, such as meters or Kilograms.