Decimal → Roman Numeral
Convert a decimal integer to a Roman numeral. Standard range: 1 to 3999.
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About Decimal → Roman Numeral
Roman numerals use seven symbols (I, V, X, L, C, D, M) and a subtractive notation (IV = 4, IX = 9) to represent integers from 1 to 3999. They're still used in clock faces, monarch numbering, copyright years, and outline numbering. This tool produces the canonical form (e.g. MCMXCIV, not MDCCCCLXXXXIIII).
When to use it
- Converting copyright years to Roman numerals (1994 → MCMXCIV)
- Producing chapter or section numbers in outlines
- Generating Roman numeral years for clocks or monuments
How it works
A greedy algorithm processes the seven Roman symbol values (plus the four subtractive pairs CM, CD, XC, XL, IX, IV) from largest to smallest, repeatedly subtracting and appending until the number reaches zero.
Examples
4
IV
1994
MCMXCIV
3999
MMMCMXCIX
Frequently asked questions
- Why is the maximum 3999?
- Standard Roman numeral notation only goes up to MMMCMXCIX (3999). Larger numbers historically used overlines (V̄ = 5000) which Unicode supports but most fonts don't render well.
- Are 0 and negative numbers supported?
- No. Romans had no zero (it was added to European math much later) and didn't use negative numbers.