Roman Numeral Converter

Convert numerals

Valid range: 1 to 3999

How Roman Numeral Conversion Works

The Roman Numeral Converter translates between standard Arabic numbers and Roman numerals in both directions. It handles values from 1 to 3,999 and validates input to ensure correct Roman numeral formatting according to traditional rules.

Formula

I=1, V=5, X=10, L=50, C=100, D=500, M=1000

Key Features

  • Convert Arabic numbers to Roman numerals and back
  • Supports values from 1 (I) to 3999 (MMMCMXCIX)
  • Input validation with error messaging
  • Explains the Roman numeral system with examples

Pro Tip

Roman numerals use subtractive notation for 4 and 9 patterns: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900. A smaller numeral before a larger one means subtraction.

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