Abstract: Optical character recognition systems and methods including the steps of: capturing an image of a document including a set of numbers having a defined mathematical relationship; analyzing the image to determine line segments; analyzing each line segment to determine one or more character segments; analyzing each character segment to determine possible interpretations, each interpretation having an associated predicted probability of being accurate; forming a weighted finite state transducer for each interpretation, wherein the weights are based on the predicted probabilities; combining the weighted finite state transducer for each interpretation into a document model weighted finite state transducer that encodes the defined mathematical relationship; searching the document model weighted finite state transducer for the lowest weight path, which is an interpretation of the document that is most likely to accurately represent the document; and outputting an optical character recognition version of the captured