Roman Numeral Converter

Convert standard decimal numbers to classical Roman numerals (from 1 to 3999) and vice versa instantly.

Decimal Number (1 - 3999)
Roman Numeral (I, V, X, L, C, D, M)
R

Key Symbol Values

I1
V5
X10
L50
C100
D500
M1000

💡 Form Rules Reference

  • Subtractive logic: Smaller symbols placed before larger symbols are subtracted (e.g., IV = 4, IX = 9, XC = 90).
  • Sequential limits: A symbol cannot be repeated more than 3 times in consecutively formatted streams (e.g., 40 is XL, not XXXX).

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