Roman Numeral Converter
Convert between Arabic numbers (1-3999) and Roman numerals.
Roman Numeral Reference
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What is this tool?
Roman numeral converter transforms between Arabic numbers (1, 2, 3...) and Roman numerals (I, II, III...). Supports conversion in both directions for numbers 1 to 3999. Roman numerals use seven symbols: I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Still used in clock faces, book chapters, movie credits, and monarch numbering.
How to use
- 1
Enter number
Type an Arabic number or Roman numeral.
- 2
Get conversion
See the result in the other format instantly.
- 3
View results
Review the output.
Frequently Asked Questions
Why does Roman numerals stop at 3999?
Standard Roman numerals use M (1000) as the largest symbol. Numbers above 3999 require a bar above the symbol (multiplying by 1000), which is not practical in plain text. For example, 5000 would be V with a bar (V̅).
How is 4 represented?
4 is IV: I before V means 5 minus 1.
How accurate are the conversions?
Conversions use standard conversion factors with high precision. For scientific applications use certified tools.
How do I type Roman numerals on a computer?
There is no dedicated key or character set on standard keyboards, so the easiest route is to type the Arabic number and convert it. Enter a value from 1 to 3999 in this tool and it returns the Roman form (MMXXVI for 2026, for example) that you can copy straight into a document; the tool converts in both directions. Alternatively, just type the letters I, V, X, L, C, D, M directly: most fonts render them correctly.