Roman Numeral Converter
Convert numbers to Roman numerals and Roman numerals back to numbers.
What the Roman Numeral Converter does
Roman numerals combine seven letters. Symbols are added when they descend in value and subtracted when a smaller one precedes a larger, which is why 4 is IV rather than IIII.
Formula
I=1, V=5, X=10, L=50, C=100, D=500, M=1000Subtractive pairs: IV, IX, XL, XC, CD, CM
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| Direction | one of 2 options | Yes | — |
| Number (1–3999) | number | In some modes | Accepts 1 or more, up to 3999. Shown Direction is Number → Roman numeral. |
| Roman numeral | text | In some modes | Shown Direction is Roman numeral → Number. |
How to use it
- Choose Direction.
- Fill in the remaining inputs the form shows for your choice.
- Select Calculate.
Worked example
Write 1994 as a Roman numeral.
- Number
- 1994
MCMXCIV — M (1000) + CM (900) + XC (90) + IV (4).
Frequently asked questions
Why do Roman numerals stop at 3999?
Without an overline notation for thousands there is no way to write 4000, since MMMM is not standard form.
Is there a zero?
No. The Roman system has no symbol for zero — the concept arrived in Europe much later.