Roman Numeral Converter
Convert Arabic numbers to Roman numerals and vice versa instantly. Our free online tool supports numbers 1-3999 with real-time validation and copy-to-clipboard functionality.
Convert between Arabic numbers (1-3999) and Roman numerals instantly
- • Roman numerals use letters: I(1), V(5), X(10), L(50), C(100), D(500), M(1000)
- • Subtractive notation: IV(4), IX(9), XL(40), XC(90), CD(400), CM(900)
- • Maximum value: 3999 (MMMCMXCIX)
Quick Examples
Common number conversions to get you started
About Roman Numerals
Roman numerals are a numeral system that originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. They are still used today in various contexts, including clock faces, book chapters, movie sequels, and formal documents.
Our Roman numeral converter makes it easy to convert between modern Arabic numbers (1, 2, 3, etc.) and their Roman numeral equivalents (I, II, III, etc.). The tool handles all standard Roman numeral rules, including subtractive notation like IV for 4 and IX for 9.
Whether you're working on homework, creating formal documents, or just curious about Roman numerals, our converter provides accurate, instant results with detailed validation to ensure you get the correct format every time.
Why Use Our Converter?
See results instantly as you type. No need to click convert buttons or wait for page refreshes.
Convert from Arabic numbers to Roman numerals or from Roman numerals to Arabic numbers with equal ease.
Our tool validates inputs and provides clear error messages for invalid Roman numerals or out-of-range numbers.
Works perfectly on all devices with a responsive design that adapts to your screen size.