Roman numeral converter
Convert any number from 1 to 3,999 into Roman numerals, or turn Roman numerals back into a number.
About this calculator
Type a number to see it in Roman numerals, or type Roman numerals to see the number. Only valid numerals written in the standard way are accepted.
Roman numerals use seven letters: I, V, X, L, C, D and M.
Measurements and terms explained
- I, V, X
- 1, 5 and 10.
- L, C
- 50 and 100.
- D, M
- 500 and 1,000.
- Subtractive notation
- A smaller letter before a larger one is subtracted, so IV is 4 and IX is 9.
Common questions
What is the biggest Roman numeral?
MMMCMXCIX is 3,999. Larger numbers needed a bar over the letters, which is not covered here.
Is there a zero?
No. The Romans had no symbol for zero.
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