Roman Numeral Converter: I, V, X, L, C, D, M Explained
Roman numerals show up on clocks, movie credits, book chapters, and Super Bowl numbers. Converting between Arabic (1, 2, 3) and Roman (I, II, III) numbers is simple in principle but error-prone for larger values.
Roman numerals use seven letters: I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Numbers are formed by combining them — VIII = 8, XXVII = 27. The system uses subtraction for certain combinations: IV = 4 (one less than V), IX = 9, XL = 40, XC = 90, CD = 400, CM = 900.
Common Roman numerals
| Arabic | Roman |
|---|---|
| 1 | I |
| 5 | V |
| 10 | X |
| 50 | L |
| 100 | C |
| 500 | D |
| 1000 | M |
| 4 | IV |
| 9 | IX |
| 40 | XL |
| 90 | XC |
| 400 | CD |
| 900 | CM |
| 2026 | MMXXVI |
| 1999 | MCMXCIX |
| 2024 | MMXXIV |
Extended FAQ
Can Roman numerals represent zero?
No — there's no Roman numeral for zero. The concept of zero arrived in Europe much later via Indian and Arab mathematicians.
What's the largest Roman numeral?
Conventional notation maxes around 3,999 (MMMCMXCIX). Higher numbers used a bar over a letter (V̄ = 5,000) but conventions varied.
Are my values stored?
No — runs entirely in your browser.