Roman Numerals Converter
Convert Arabic numbers and Roman numerals both ways in real time, with breakdown, batch mode and a reference chart
Free to useOpen and use right awayText Tools
Converts as you type. Standard Roman numerals cover integers from 1 to 3999.
Lenient mode accepts non-standard forms such as IIII and allows values above 3999
Enter a number or a Roman numeral — the result appears here instantly
Roman numeral reference
Basic symbols
| Symbol | Value |
|---|---|
| I | 1 |
| V | 5 |
| X | 10 |
| L | 50 |
| C | 100 |
| D | 500 |
| M | 1,000 |
Common examples
Click any example to load it into the input above
How Roman numerals work
- Roman numerals combine seven symbols — I, V, X, L, C, D and M. The same symbol repeats at most three times: III = 3, XXX = 30, MMM = 3000.
- A smaller symbol placed before a larger one is subtracted (IV = 4, IX = 9, XC = 90); placed after, it is added (VI = 6).
- Only I, X and C may be subtracted, each from the next two values: IV / IX, XL / XC, CD / CM.
- Symbols run from the largest value to the smallest: MCMXCIV = 1000 + 900 + 90 + 4 = 1994.
- Classic Roman numerals have no zero and cover 1 to 3999 — enable lenient mode for larger values.