Roman numeral converter
Type a number to get the numeral, or type a numeral to get the number — both fields work, and each one updates the other as you go.
How to use the roman numeral converter
- Enter a number in the first field, or a numeral in the second.
- Read the converted value in the other field.
- Check the validity note if you typed the numeral yourself.
How it works
Roman numerals use seven letters: I, V, X, L, C, D and M for 1, 5, 10, 50, 100, 500 and 1,000. Values are added left to right, except when a smaller letter precedes a larger one, which subtracts — IV is 4 and IX is 9. That subtractive rule is why 1994 is MCMXCIV rather than a long string of Ms and Cs.
Above 3,999 an overline traditionally multiplies a letter by a thousand, shown here as a bar over the character. There is no symbol for zero and no way to write a fraction, which is one reason the system was eventually abandoned for arithmetic.
Common questions
What is 2026 in Roman numerals?
MMXXVI — two thousands, two tens, a five and a one.
Why is 4 written IV and not IIII?
The subtractive rule shortens repeated letters. IIII does still appear on some clock faces, by tradition rather than by rule.