Roman Numeral Converter
Convert Arabic numbers to Roman numerals and back — with step-by-step breakdown.
Roman Numeral Reference
How Roman numeral conversion works
Roman numerals use seven symbols. Numbers are formed by combining symbols and adding values. When a smaller value precedes a larger, it is subtracted (subtractive notation).
VI = 5 + 1 = 6. Symbols of equal or decreasing value are added together.
IV = 5 − 1 = 4. IX = 9, XL = 40, XC = 90, CD = 400, CM = 900.
Standard Roman numerals cover 1–3999. 4000 would require a vinculum (overline) notation.
Frequently asked questions
What is the largest Roman numeral?
Using standard notation (no overline), the largest is 3999 = MMMCMXCIX. The number 4000 requires a special overline notation (M̄) or alternative systems.
Why is there no zero in Roman numerals?
Roman numerals were developed for counting physical objects, where zero had no practical meaning. The concept of zero as a placeholder was introduced later through Indian and Arab mathematics.
What year is MMXXIV?
MMXXIV = 2000 + 20 + 4 = 2024. MM = 2000, XX = 20, IV = 4.
Are Roman numerals still used today?
Yes — in clock faces, movie credits, chapter numbers, Super Bowl designations, monarchs (King Charles III), and copyright years.
What are the six subtractive pairs?
IV (4), IX (9), XL (40), XC (90), CD (400), CM (900). These are the only valid subtractive combinations in standard Roman numerals.