DigiKitRoman Numeral Converter
Type a number (e.g. 1994) or a Roman numeral (e.g. MCMXCIV) to convert it instantly.
What are Roman numerals?
Roman numerals are the number system of ancient Rome. They still appear in century names, clock faces, book chapters, monarch names (Elizabeth II) and film credits. This tool works both ways: type a number to get the numeral, or type a numeral to get the number.
Basic symbols
| Symbol | Value |
|---|---|
| I | 1 |
| V | 5 |
| X | 10 |
| L | 50 |
| C | 100 |
| D | 500 |
| M | 1000 |
Writing rules
- The same symbol is repeated at most three times in a row: III=3, XXX=30.
- A smaller value placed before a larger one is subtracted: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900.
- Only I, X and C are used for subtraction; V, L and D are never placed before.
- Read from left to right, largest to smallest: MCMXCIV = 1000 + 900 + 90 + 4 = 1994.
Examples
| Number | Roman |
|---|---|
| 4 | IV |
| 9 | IX |
| 14 | XIV |
| 49 | XLIX |
| 99 | XCIX |
| 444 | CDXLIV |
| 1994 | MCMXCIV |
| 2026 | MMXXVI |
| 3999 | MMMCMXCIX |
How to use it
- Type a number (e.g. 2026) or a Roman numeral (e.g. MMXXVI) in the box.
- Press Run to see the result.
- Lowercase works; the tool converts to uppercase. Invalid sequences (IIII, VX) trigger a warning.
Limits
The tool supports 1 to 3999, because the standard system needs more than three Ms for 4000 and above. There is no Roman numeral for zero or for decimals.
Reading a year in Roman numerals
Film credits and old buildings often show the year in Roman numerals. The quickest way to read one is to split it into thousands, hundreds, tens and ones. MCMLXXXVII becomes M (1000) + CM (900) + LXXX (80) + VII (7) = 1987. Going the other way, 1999 is M + CM + XC + IX = MCMXCIX, while 2000 is simply MM.
You may also notice that many clock faces show four as IIII rather than IV. That is not a mistake but a long-standing clockmaking tradition, so do not be surprised if a clock and this tool disagree.
Frequently asked questions
How do you read Roman numerals?
Seven letters are used: I=1, V=5, X=10, L=50, C=100, D=500, M=1000. A smaller value before a larger one is subtracted (IV=4); after it, it is added (VI=6).
How do you write 2026 in Roman numerals?
MMXXVI: MM=2000, XX=20, VI=6, total 2026.
What is the largest number?
With the standard rules up to 3999 (MMMCMXCIX). Larger numbers use overlined notation, which the tool does not support.
Is there a zero in Roman numerals?
No. Roman numerals have no symbol for zero.