Roman Numeral Converter

Convert between regular numbers and Roman numerals. Supports values from 1 to 3999 using standard modern Roman numeral rules.

Number to Roman numeral

Enter an integer between 1 and 3999 to convert it to a Roman numeral.

Number → Roman

Example: 2025 → MMXXV

Roman numeral to number

Use letters I, V, X, L, C, D, M. The tool validates standard subtractive forms (IV, IX, XL, XC, CD, CM).

Roman → Number

The converter will reject invalid or non-standard Roman numeral combinations.

Quick Roman numeral rules

Basic symbols: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1000.
Write largest values first, left to right, adding them together (e.g., VIII = 5 + 3 = 8).
Place a smaller numeral before a larger one to subtract (e.g., IV = 4, IX = 9, XL = 40, CM = 900).
Common modern range is 1–3999 (I to MMMCMXCIX).

Historically, there were variations in how Romans wrote numbers. This tool uses a consistent modern rule set that's commonly taught in schools and used in software.

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