Roman Numeral Converter
Convert between Arabic and Roman numerals.
Arabic Number (1-3999)
Roman Numeral
Advertisement
Convert Arabic numbers to Roman numerals and vice versa instantly. This history and math tool runs entirely client-side in your browser.
How to use it
- Enter a number between 1 and 3999, or a Roman numeral.
- Convert in the direction you need.
- Copy the result.
Frequently asked questions
Why does it stop at 3999?
Because standard notation has no symbol above M for a thousand. Larger values needed an overline to multiply a numeral by a thousand, which plain text cannot show.
How does subtractive notation work?
A smaller symbol before a larger one is subtracted: IV is four, IX is nine, XL is forty, CM is nine hundred. Only I, X and C are used this way.
Is there a Roman numeral for zero?
No. The system has no zero and no negative numbers, which is precisely why arithmetic with it is so awkward.