A conversion function for converting between the euro and other currencies is provided that converts a value in one type of currency to a value in another type of currency according to EU-specified conversion rules and rounding rules. The conversion function may utilize full-precision computation or may convert the value utilizing a user-supplied number of significant digits. A method and apparatus for formatting the results of a conversion in a user-modifiable euro style is also provided. A formatting toolbar button is supplied that when selected applies a euro style to a selected currency value or range of values. A conversion wizard for converting a group of values or functions between the euro and other currencies is also provided. The wizard permits user-selected formula handling options to be selected at the time of conversion. A toolbar for viewing the results of the conversion is also provided. The toolbar provides a floating window that indicates the value of a current location in a user-specified type of currency. The window is updated each time a new location or range of locations is selected, a refresh command is issued, or a new type of currency is selected.