A method and apparatus for recognizing an input identifier on the basis of a set of comparison identifiers. After a user provides the input identifier according to a first form, the present invention provides a recognized identifier based on the input identifier. The present invention then generates a plurality of comparison identifiers on the basis of the recognized identifier. The user is then prompted to provide the input identifier again, but this time according to a second form that is different than the first form. A second recognized identifier is then generated on the basis of the input identifier provided according to the second form. If a match exists between the second recognized identifier and one of the comparison identifiers, the matched comparison identifier is selected as corresponding to the input identifier.