Number to Roman Numeral Converter
Convert numbers to Roman numerals, or Roman numerals back to numbers.
Roman numerals still show up on clocks, movie credits, book chapters, and monument dates — this converts numbers to Roman numerals and back, both directions.
The subtractive notation rule
Roman numerals use a subtractive shortcut for certain numbers — instead of writing IIII for 4, it's written IV (one less than five). This pattern (IV, IX, XL, XC, CD, CM) is what makes reading and converting Roman numerals trickier than it first appears.
Frequently asked questions
What's the largest number standard Roman numerals can represent?
The standard system comfortably represents up to 3,999 (MMMCMXCIX) — numbers beyond that traditionally require special notation with bars over letters to indicate multiplication by 1,000.
Why do movie copyright years use Roman numerals?
It's largely a stylistic and historical convention in the film industry, sometimes said to make the exact release year slightly less immediately obvious to casual viewers.