Roman Numeral Converter
Convert between Arabic numbers and Roman numerals in both directions (1–3999).
Quick Examples
About This Tool
The Roman Numeral Converter converts between Arabic numbers (1–3999) and Roman numerals in both directions. Enter an Arabic number to get the Roman numeral, or type a Roman numeral to get its decimal value.
Uses standard subtractive notation: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900. Base symbols: I=1, V=5, X=10, L=50, C=100, D=500, M=1000.
How to Use
- Select the direction: Arabic → Roman or Roman → Arabic.
- Enter a number (1–3999) or a Roman numeral (e.g., MMXXIV).
- Click Convert or press Enter to see the result.
- Click any example button for quick common conversions.
Use Cases
Students and educators use this when studying classical history, Latin, or ancient number systems. Clock enthusiasts, book publishers, and filmmakers use it to encode copyright years in Roman numerals.
FAQ
- What is the largest number in Roman numerals? — Standard Roman numerals go up to 3999 (MMMCMXCIX). Higher values require extensions like a vinculum (bar over a symbol) which are not standard.
- Is IIII valid? — On some clock faces yes, but by strict rules no. Subtractive notation (IV) is standard; IIII is a historical variant.
- What year is MMXXIV? — 2024. MM = 2000, XX = 20, IV = 4.