Roman Numeral Converter
The Roman Numeral Converter translates between ordinary numbers and Roman numerals (I, V, X, L, C, D, M) in either direction, for any value from 1 to 3,999.
How Roman numerals work
Roman numerals combine seven letters - I (1), V (5), X (10), L (50), C (100), D (500), M (1000) - using addition and subtraction. A smaller letter before a larger one subtracts (IV = 4, IX = 9, XL = 40), while a smaller letter after a larger one adds (VI = 6, XV = 15). The converter builds and reads these rules automatically.
Why the limit is 3,999
Standard Roman numerals only go up to 3,999 (MMMCMXCIX) because there is no single symbol for 5,000 or 10,000 in the classic system. This tool is perfect for reading clock faces, book chapters, film copyright dates, monarch names, and Super Bowl numbers.
Frequently Asked Questions
Why can't Roman numerals go above 3,999?
The classic system has no standard symbol beyond M (1000), so the largest value expressible with normal letters is 3,999, written MMMCMXCIX.
How does subtractive notation work?
A smaller symbol placed before a larger one is subtracted: IV is 4, IX is 9, XL is 40, and CM is 900.
Can it convert both ways?
Yes. Enter a number to get the Roman numeral, or enter a Roman numeral to get the number.
Is there a Roman numeral for zero?
No. The Roman system has no symbol for zero, which is why conversions start at 1.
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