Online Roman Numeral Converter
Convert integers to roman numerals and back, supports 1-3999, strictly follows standard subtractive notation, fully client-side
FAQ
Integers from 1 to 3999. Roman numerals have no zero and no standard form above 3999, so out-of-range values are flagged as invalid.
Standard roman numerals follow subtractive notation: 4 is IV not IIII. The tool validates input by round-trip conversion and rejects non-standard forms like IIII, VX and IC.
No. All conversion happens locally in your browser. Your data never leaves your device, keeping your privacy fully protected.
Yes. Input is automatically converted to uppercase, so typing mmxxiv returns 2024.
Clock faces, movie sequels (e.g. Star Wars IV), book chapters, commemorative years (MMXXIV = 2024), and royal or papal names.
Completely free. This is a pure frontend online tool - no registration required, no payment needed, just open and use.
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