Roman Numeral Converter

Convert between Roman numerals and Arabic numbers (1–3999). Includes input validation and examples.

Inputs
Rules:
  • Allowed symbols: I, V, X, L, C, D, M
  • Subtractive notation: IV(4), IX(9), XL(40), XC(90), CD(400), CM(900)
  • Maximum 3999 (MMMCMXCIX)
Result
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