🏛️ Roman Numeral Converter
Roman numerals still show up on clocks, in film credits, for numbering chapters and on buildings. Enter a number between 1 and 3999 and this calculator instantly converts it to the correct Roman form, built according to the classic subtractive rules.
Roman numeral
MCMXCIV
Formula
Subtract the largest symbols first, smallest last
Roman numerals use seven base symbols: I=1, V=5, X=10, L=50, C=100, D=500, M=1000. The number is built by repeatedly subtracting the largest possible symbol, where combinations like IV (4) and IX (9) place a smaller symbol before a larger one to indicate subtraction.
Steps
- 1Enter a whole number between 1 and 3999.
- 2The calculator repeatedly subtracts the largest possible symbol, from M down to I.
- 3Read off the complete Roman numeral as the result.
Roman base symbols
| Symbol | Value | Example combination |
|---|---|---|
| I | 1 | IV = 4 |
| V | 5 | VIII = 8 |
| X | 10 | XL = 40 |
| L | 50 | LX = 60 |
| C | 100 | CM = 900 |
| D | 500 | DC = 600 |
| M | 1000 | MM = 2000 |
The seven base symbols; every Roman numeral between 1 and 3999 is built from these.
commonMistakes
- Assuming any symbol can repeat indefinitely; IIII for 4 is wrong, IV is correct.
- Repeating a symbol more than three times in a row, such as XXXX instead of XL for 40.
- Combining two subtractive symbols that isn't allowed, such as IL for 49 instead of XLIX.
useCases
- Looking up a year or chapter number in Roman numerals.
- Composing an engraving text for a watch, ring or monument.
- Recognizing the episode or season number of a show written in Roman numerals.