Roman numeral converter
Type an Arabic number or a Roman numeral; the conversion runs the other way automatically. Standard Roman numerals cover 1-3999, because there is no ordinary symbol above M.
The converter uses the modern subtractive notation found in textbooks: 4 is IV, not IIII. Ancient inscriptions and clock faces sometimes use the additive form, equally correct historically.
Frequently asked questions
Why do clocks write IIII instead of IV?
A clockmakers' convention: IIII visually balances the VIII opposite it on the dial. Both notations are correct.
How are numbers above 3999 written?
Romans drew a line over a symbol (the vinculum) to multiply it by a thousand: V with a bar is 5000. There is no single modern typographic form for it, hence the 3999 limit.
Did the Roman system have a zero?
No. Roman numerals have no symbol for zero and no place value, which makes multiplication and division very awkward — the reason Europe switched to Arabic numerals.