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Roman Numeral Converter
Convert numbers to Roman numerals and back, either way.
Result
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Converts either way.
| Input | — |
|---|---|
| Interpreted as | — |
| Value | — |
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Enter your figures above to see the step-by-step working.
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How the Roman Numeral Converter Works
Roman numerals build numbers from seven letters — I (1), V (5), X (10), L (50), C (100), D (500) and M (1000) — combined largest-first and added up, with a smaller letter before a larger one meaning subtraction (IV is 4, IX is 9, XL is 40). This converter works both ways: type a number (1–3999) to get the numerals, or type numerals to get the number.
The standard system only goes up to 3,999 (MMMCMXCIX) because there’s no single letter for 5,000, which is why years and clock faces are its most common modern use.
I=1, V=5, X=10, L=50, C=100, D=500, M=1000 (smaller-before-larger subtracts)
Frequently Asked Questions
How do you write a number in Roman numerals?
Break it into thousands, hundreds, tens and units and write each with the letters, largest first. 2024 is MMXXIV: MM (2000) + XX (20) + IV (4).
What is the largest Roman numeral?
In the standard system, 3,999 — MMMCMXCIX. There’s no standard single letter for 5,000, so it stops there.
What does IV and IX mean?
A smaller numeral before a larger one is subtracted: IV is 5−1 = 4, and IX is 10−1 = 9.
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