Roman numerals converter
Type a number or a Roman numeral. The other box fills in.
What you enter stays on this page and is not sent anywhere.
How to use it
- Type a number in the first box, or a Roman numeral in the second.
- Read the converted value. A message explains anything that cannot be converted.
- Copy the Roman numeral, or press Use this year.
Questions
Why does it stop at 3999?
Standard Roman numerals use the letters I, V, X, L, C, D and M, and M repeated more than three times is not part of the standard form. Larger numbers need an overline, which this tool does not use.
Why is IIII or IC rejected?
The tool reads standard numerals only: 4 is IV, 9 is IX and 99 is XCIX. Forms such as IIII appear on some clock faces, but are not the standard form.
How are Roman numerals read?
Letters are added, except that a smaller letter placed before a larger one is subtracted. So IX is 10 minus 1, and MCMXCIV is 1000 plus 900 plus 90 plus 4.
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