Roman Numeral Converter
Convert numbers to Roman numerals and back. Learn the symbols and values for I, V, X, L, C, D, and M. Supports values from 1 to 3,999.
How Roman Numerals Work
Roman numerals are a numeral system that originated in ancient Rome. Numbers are written by combining symbols from the table above.
Rules of Construction
- Addition: When a symbol appears after a larger (or equal) symbol, it is added.
Example: VI = 5 + 1 = 6. - Subtraction: When a symbol appears before a larger symbol, it is subtracted.
Example: IV = 5 - 1 = 4. - Repetition: The symbols I, X, C, and M can be repeated up to three times in a row. V, L, and D are never repeated.
Examples
- 2024: MMXXIV (1000+1000 + 10+10 + 5-1)
- 1999: MCMXCIX (1000 + 1000-100 + 100-10 + 10-1)
- 49: XLIX (50-10 + 10-1)
? Frequently Asked Questions
The Romans did not have a symbol for zero. They used words like 'nulla' (none) to describe the concept, but it wasn't part of the numeral system.
In standard notation, the largest number is 3,999 (MMMCMXCIX). For larger numbers, a vinculum (overline) was historically used to multiply values by 1,000, but standard keyboards don't support this easily.
While 'IIII' was sometimes used (and still appears on some clock faces), the subtractive notation 'IV' became standard to keep numbers shorter and easier to read.