Roman Numeral Converter

About this calculator

This tool converts an ordinary Arabic numeral (1–3999) into Roman numerals using the standard subtractive notation — repeated symbols like III for 3, and subtractive pairs like IV for 4 or IX for 9 — following the same rules the Romans and, later, medieval scribes standardized.

Roman numerals are still used today in specific, mostly ceremonial or stylistic contexts: clock and watch faces, book chapter and outline numbering, movie sequel and Super Bowl numbering, monarch and pope regnal numbers (Elizabeth II, Louis XIV), and copyright dates on film credits. Anyone needing to write one of these correctly — or trying to read a date engraved in Roman numerals on a building or a movie's copyright notice — uses a converter like this instead of working out the subtraction rules by hand.