Roman Numeral Converter
Convert numbers to Roman numerals and back.
Number → Roman
MMXXIV
How Roman numerals work
Roman numerals combine seven letters — I (1), V (5), X (10), L (50), C (100), D (500), and M (1000). Symbols are added when written largest-to-smallest, and subtracted when a smaller symbol precedes a larger one (IV = 4, IX = 9, CM = 900). The standard system represents 1 through 3999. This converter auto-detects whether you typed a number or a numeral, and validates that numerals are well-formed before converting — all in your browser.
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